Summary of Significant Accounting Policies: Basis of Presentation (Policies)	12 Months Ended
Sep. 30, 2020
Accounting Policies [Abstract]
Principles of Consolidation	The accompanying consolidated financial statements include the accounts of Timberland Bancorp, Inc. (“Timberland Bancorp”); its wholly owned subsidiary, Timberland Bank (the “Bank”); and the Bank’s wholly owned subsidiary, Timberland Service Corp. (collectively, the "Company”). All significant intercompany transactions and balances have been eliminated in consolidation.
Nature of Operations	Timberland Bancorp is a bank holding company which operates primarily through its subsidiary, the Bank. The Bank was established in 1915 and, through its 24 branches located in Grays Harbor, Pierce, Thurston, Kitsap, King and Lewis counties in Washington State, attracts deposits from the general public, and uses those funds, along with other borrowings, primarily to provide residential real estate, construction, commercial real estate, commercial business and consumer loans to borrowers primarily in western Washington.
Consolidated Financial Statement Presentation	The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S.") (“GAAP”) and prevailing practices within the banking industry.
Use of Estimates	The preparation of consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities, as of the date of the consolidated balance sheets, and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to the determination of the allowance for loan losses, the determination of any OTTI in the fair value of investment securities, the valuation of servicing rights, the valuation of OREO, the valuation of assets acquired and liabilities assumed in acquisitions and the valuation of goodwill for potential impairment.
Reclassification Policy	Certain prior year amounts have been reclassified to conform to the 2020 fiscal year presentation with no change to previously reported net income or shareholders’ equity.
Segment Reporting	The Company has one reportable operating segment which is defined as community banking in western Washington under the operating name “Timberland Bank.”
Cash and Cash Equivalents and Cash Flows	The Company considers amounts included in the consolidated balance sheets’ captions “Cash and due from financial institutions” and “Interest-bearing deposits in banks,” all of which mature within ninety days, to be cash equivalents for purposes of reporting cash flows.
CDs Held for Investment	CDs held for investment include amounts invested with other FDIC-insured financial institutions for a stated interest rate and with a fixed maturity date. Such CDs generally have maturities of 12 to 60 months from the date of purchase by the Company. Early withdrawal penalties may apply; however, the Company intends to hold these CDs to maturity. The Company generally limits its purchases of CDs to a maximum of $250,000 (the FDIC insurance coverage limit) with any single financial institution.
Investment Securities	Investments in debt securities are classified upon acquisition as held to maturity or available for sale. Investments in debt securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and reported at amortized cost. Investments in debt securities classified as available for sale are reported at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income (loss), net of income tax effects. Premiums and discounts are amortized to interest income using the interest method over the contractual lives of the securities. Gains and losses on sales of investment securities are recognized on the trade date and determined using the specific identification method. In estimating whether there are any OTTI losses, management considers (1) the length of time and the extent to which the fair value has been less than amortized cost, (2) the financial condition and near term prospects of the issuer, (3) the impact of changes in market interest rates and (4) the intent and ability of the Company to retain its investment for a period of time sufficient to allow for any anticipated recovery in fair value. Declines in the fair value of individual debt securities available for sale that are deemed to be other than temporary are recognized in earnings when identified. The fair value of the debt security then becomes the new cost basis. For individual debt securities that are held to maturity which the Company does not intend to sell, and it is not more likely than not that the Company will be required to sell before recovery of its amortized cost basis, the other than temporary decline in the fair value of the debt security related to: (1) credit loss is recognized in earnings and (2) market or other factors is recognized in other comprehensive income (loss). Credit loss is recorded if the present value of expected future cash flows is less than the amortized cost. For individual debt securities which the Company intends to sell or more likely than not will not recover all of its amortized cost, the OTTI is recognized in earnings equal to the entire difference between the debt security’s cost basis and its fair value at the consolidated balance sheet date. For individual debt securities for which credit loss has been recognized in earnings, interest accruals and amortization and accretion of premiums and discounts are suspended when the credit loss is recognized. Interest received after accruals have been suspended is recognized on a cash basis.
FHLB Stock	The Bank, as a member of the FHLB, is required to maintain an investment in capital stock of the FHLB in an amount equal to 0.12% of the Bank's total assets plus 4.00% of any borrowings from the FHLB. No ready market exists for this stock, and it has no quoted market value. However, redemption of FHLB stock has historically been at par value. The Company's investment in FHLB stock is carried at cost, which approximates fair value. The Company evaluates its FHLB stock for impairment as needed. The Company's determination of whether this investment is impaired is based on its assessment of the ultimate recoverability of cost rather than by recognizing temporary declines in value. The determination of whether a decline affects the ultimate recoverability of cost is influenced by criteria such as (1) the significance of any decline in net assets of the FHLB as compared with the capital stock amount and the length of time any decline has persisted; (2) commitments by the FHLB to make payments required by law or regulation and the level of such payments in relation to the operating performance of the FHLB; (3) the impact of legislative and regulatory changes on institutions and, accordingly, the customer base of the FHLB; and (4) the liquidity position of the FHLB. Based on its evaluation, the Company determined that there was no impairment of FHLB stock at September 30, 2020 and 2019.
Loans Held for Sale	Mortgage loans and commercial business loans originated and intended for sale in the secondary market are stated in the aggregate at the lower of cost or estimated fair value. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. Gains or losses on sales of loans are recognized at the time of sale. The gain or loss is the difference between the net sales proceeds and the recorded value of the loans, including any remaining unamortized deferred loan origination fees.
Loans Receivable	Loans are stated at the amount of unpaid principal, reduced by the undisbursed portion of construction loans in process, net deferred loan origination fees and the allowance for loan losses.
Interest on Loans, Non-accrual Loans and Loan Fees	Interest on loans is accrued daily based on the principal amount outstanding. Generally, the accrual of interest on loans is discontinued when, in management’s opinion, the borrower may be unable to make payments as they become due or when they are past due 90 days as to either principal or interest (based on contractual terms), unless the loan is well secured and in the process of collection. In determining whether a borrower may be able to make payments as they become due, management considers circumstances such as the financial strength of the borrower, the estimated collateral value, reasons for the delays in payments, payment record, the amounts past due and the number of days past due. All interest accrued but not collected for loans that are placed on non-accrual status or charged off is reversed against interest income. Subsequent collections on a cash basis are applied proportionately to past due principal and interest, unless collectability of principal is in doubt, in which case all payments are applied to principal. Loans are returned to accrual status when the loan is deemed current, and the collectability of principal and interest is no longer doubtful, or, in the case of one- to four-family loans, when the loan is less than 90 days delinquent. The categories of non-accrual loans and impaired loans overlap, although they are not identical. The Company charges fees for originating loans. These fees, net of certain loan origination costs, are deferred and amortized to income on the level-yield basis over the loan term. If the loan is repaid prior to maturity, the remaining unamortized deferred loan origination fee is recognized in income at the time of repayment.
Troubled Debt Restructured Loans	A troubled debt restructured loan ("TDR") is a loan for which the Company, for reasons related to a borrower’s financial difficulties, grants a concession to the borrower that the Company would not otherwise consider. Examples of such concessions include, but are not limited to: a reduction in the stated interest rate; an extension of the maturity at an interest rate below current market rates; a reduction in the face amount of the debt; a reduction in the accrued interest; or re-amortizations, extensions, deferrals and renewals. TDRs are considered impaired and are individually evaluated for impairment. TDRs are classified as non-accrual (and considered to be non-performing) unless they have been performing in accordance with modified terms for a period of at least six months. In March 2020, the Company announced loan modification programs to support and provide relief for its borrowers during the novel coronavirus of 2019 ("COVID-19") pandemic. The Company has followed the loan modification criteria within the Coronavirus Aid, Relief, and Economic Security Act of 2020 ("CARES Act"), which was signed into law on March 27, 2020 and interagency guidance from the federal banking agencies when determining if a borrower's modification is subject to a TDR classification. If it is determined that the modification does not meet the criteria under the CARES Act or interagency guidance to be excluded from TDR classification, the Company evaluates the loan modifications under its existing TDR framework. Loans subject to forbearance under the COVID-19 loan modification program are not reported as past due or placed on non-accrual status during the forbearance time period, and interest income continues to be recognized over the contractual life of the loans.
Allowance for Loan Losses	The allowance for loan losses is maintained at a level sufficient to provide for probable losses inherent in the loan portfolio. The allowance is provided based upon management's comprehensive analysis of the pertinent factors underlying the quality of the loan portfolio. These factors include changes in the amount and composition of the loan portfolio, delinquency levels, actual loan loss experience, current economic conditions, and a detailed analysis of individual loans for which full collectability may not be assured. The detailed analysis includes methods to estimate the fair value of loan collateral and the existence of potential alternative sources of repayment. The allowance consists of specific and general components. The specific component relates to loans that are deemed impaired. For loans that are classified as impaired, an allowance is established when the discounted cash flows, collateral value less selling costs (if applicable), or observable market price of the impaired loan is lower than the recorded value of that loan. The general component covers non-impaired loans and is based on historical loss experience adjusted for qualitative factors. The Company's historical loss experience is determined by evaluating the average net charge-offs over the most recent economic cycle, but not to exceed six years. Qualitative factors are determined by loan type and allow management to adjust reserve levels to reflect the current general economic environment and portfolio performance trends including recent charge-off trends. Allowances are provided based on management’s continuing evaluation of the pertinent factors underlying the quality of the loan portfolio, including changes in the size and composition of the loan portfolio, actual loan loss experience, current economic conditions, collateral values, geographic concentrations, seasoning of the loan portfolio, specific industry conditions, the duration of the current business cycle, and regulatory requirements and expectations. When determining the appropriate historical loss and qualitative factors, management took into consideration the impact of the COVID-19 pandemic on such factors as the national and state unemployment rates and related trends, the amount of and timing of financial assistance provided by the government, consumer spending levels and trends, industries significantly impacted by the COVID-19 pandemic, and the Company's COVID-19 loan modification program. The appropriateness of the allowance for loan losses is estimated based upon these factors and trends identified by management at the time the consolidated financial statements are prepared. A loan is considered impaired when it is probable that the Company will be unable to collect all amounts (principal and interest) when due according to the contractual terms of the loan agreement. Smaller balance homogeneous loans, such as residential mortgage loans and consumer loans, may be collectively evaluated for impairment. When a loan has been identified as being impaired, the amount of the impairment is measured by using discounted cash flows, except when, as an alternative, the current estimated fair value of the collateral (reduced by estimated costs to sell, if applicable) or observable market price is used. The valuation of real estate collateral is subjective in nature and may be adjusted in future periods because of changes in economic conditions. Management considers third-party appraisals, as well as independent fair market value assessments from realtors or persons involved in selling real estate, in determining the estimated fair value of particular properties. In addition, as certain of these third-party appraisals and independent fair market value assessments are only updated periodically, changes in the values of specific properties may have occurred subsequent to the most recent appraisals. Accordingly, the amounts of any such potential changes and any related adjustments are generally recorded at the time such information is received. When the estimated net realizable value of the impaired loan is less than the recorded investment in the loan (including accrued interest and net deferred loan origination fees or costs), impairment is recognized by creating or adjusting an allocation of the allowance for loan losses and uncollected accrued interest is reversed against interest income. If ultimate collection of principal is in doubt, all cash receipts on impaired loans are applied to reduce the principal balance. A provision for (recapture of) loan losses is charged (credited) to operations and is added to (deducted from) the allowance for loan losses based on a quarterly comprehensive analysis of the loan portfolio. The allowance for loan losses is allocated to certain loan categories based on the relative risk characteristics, asset classifications and actual loss experience of the loan portfolio. While management has allocated the allowance for loan losses to various loan portfolio segments, the allowance is general in nature and is available for the loan portfolio in its entirety. The ultimate recovery of all loans is susceptible to future market factors beyond the Company’s control. These factors may result in losses or recoveries differing significantly from those provided in the consolidated financial statements. If real estate values decline and as updated appraisals are received on collateral for impaired loans, the Company may need to increase the allowance for loan losses appropriately. In addition, regulatory agencies, as an integral part of their examination process, periodically review the Company’s allowance for loan losses, and may require the Company to make additions to the allowance based on their judgment about information available to them at the time of their examinations.
Premises and Equipment	Premises and equipment are recorded at cost. Depreciation is computed using the straight-line method over the following estimated useful lives: buildings and improvements - five to 40 years and furniture and equipment - three to seven years. The cost of maintenance and repairs is charged to expense as incurred. Gains and losses on dispositions are reflected in earnings.
Impairment of Long-Lived Assets	Long-lived assets, consisting of premises and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the recorded amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the recorded amount of an asset to undiscounted future net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the recorded amount of the assets exceeds the discounted recovery amount or estimated fair value of the assets. No events or changes in circumstances have occurred during the years ended September 30, 2020 or 2019 that would cause management to evaluate the recoverability of the Company’s long-lived assets.
OREO and Other Repossessed Assets	OREO and other repossessed assets consist of properties or assets acquired through or in lieu of foreclosure, and are recorded initially at the estimated fair value of the properties less estimated costs of disposal, establishing a new cost basis. These assets are subsequently accounted for at lower of cost or fair value less estimated costs to sell. When the property is acquired, any excess of the loan balance over the estimated net realizable value is charged to the allowance for loan losses. The valuation of real estate is subjective in nature and may be adjusted in future periods because of changes in economic conditions. Management considers third-party appraisals, as well as independent fair market value assessments from realtors or persons involved in selling real estate, in determining the estimated fair values of particular properties. In addition, as certain of these third-party appraisals and independent fair market value assessments are only updated periodically, changes in the values of specific properties may have occurred subsequent to the most recent appraisals. Accordingly, the amounts of any such potential changes and any related adjustments are generally recorded at the time such information is received.
BOLI	BOLI policies are recorded at their cash surrender value less applicable cash surrender charges. Income from BOLI is recognized when earned.
Goodwill	Goodwill is initially recorded when the purchase price paid in a business combination exceeds the estimated fair value of the net identified tangible and intangible assets acquired and liabilities assumed. Goodwill is presumed to have an indefinite useful life and is analyzed annually for impairment. The Company performs an annual review during the third quarter of each fiscal year, or more frequently if indicators of potential impairment exist, to determine if the recorded goodwill is impaired. For purposes of goodwill impairment testing, the services offered through the Bank and its subsidiary are managed as one strategic unit and represent the Company's only reporting unit. The annual goodwill impairment test begins with a qualitative assessment of whether it is "more likely than not" that the reporting unit's fair value is less than its carrying amount. If an entity concludes that it is not "more likely than not" that the fair value of a reporting unit is less than its carrying amount, it need not perform a two-step impairment test. If the Company's qualitative assessment concluded that it is "more likely than not" that the fair value of its reporting unit is less than its carrying amount, it must perform the two-step impairment test to identify potential goodwill impairment and measure the amount of goodwill impairment loss to be recognized, if any. The first step of the goodwill impairment test compares the estimated fair value of the reporting unit with its carrying amount, or the book value, including goodwill. If the estimated fair value of the reporting unit equals or exceeds its book value, goodwill is considered not impaired, and the second step of the impairment test is unnecessary. The second step, if necessary, measures the amount of goodwill impairment loss to be recognized. The reporting unit must determine fair value for all assets and liabilities, excluding goodwill. The net of the assigned fair value of assets and liabilities is then compared to the book value of the reporting unit, and any excess book value becomes the implied fair value of goodwill. If the carrying amount of the goodwill exceeds the newly calculated implied fair value of goodwill, an impairment loss is recognized in the amount required to write-down the goodwill to the implied fair value. Management's qualitative assessment takes into consideration macroeconomic conditions, industry and market considerations, cost or margin factors, financial performance and the share price of the Company's common stock. The Company performed its fiscal year 2020 goodwill impairment test during the quarter ended June 30, 2020 with the assistance of an independent third-party firm specializing in goodwill impairment valuations for financial institutions. The third-party analysis was conducted as of May 31, 2020 and the step one test concluded that the reporting unit's fair value was more than its recorded value and, therefore, step two of the analysis was not necessary. Accordingly, the recorded value of goodwill as of May 31, 2020 was not impaired. A significant amount of judgment is involved in determining if an indicator of goodwill impairment has occurred. Such indicators may include, among others: a significant decline in expected future cash flows; a sustained, significant decline in the Company's stock price and market capitalization; a significant adverse change in legal factors or in the business climate; adverse assessment or action by a regulator; and unanticipated competition. Any change in these indicators could have a significant negative impact on the Company's financial condition, impact the goodwill impairment analysis or cause the Company to perform a goodwill impairment analysis more frequently than once per year. As of September 30, 2020, management believes that there were no events or changes in the circumstances since May 31, 2020 that would indicate a potential impairment of goodwill. No assurances can be given, however, that the Company will not record an impairment loss on goodwill in the future. If adverse economic conditions or the recent decrease in the Company's stock price and market capitalization as a result of the COVID-19 pandemic were deemed to be other than temporary, it may significantly affect the fair value of the Company's goodwill and may trigger impairment charges. Any impairment charge could have a material adverse effect on the Company's results of operation and financial condition.
MSRs	The Company holds rights to service (1) loans that it has originated and sold to the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and (2) the guaranteed portion of U.S. Small Business Administration ("SBA") loans sold in the secondary market. Servicing rights are capitalized at estimated fair value when acquired through the origination of loans that are subsequently sold with the servicing rights retained. Servicing rights are amortized to servicing income on loans sold approximately in proportion to and over the period of estimated net servicing income. The value of servicing rights at the date of the sale of loans is estimated based on the discounted present value of expected future cash flows using key assumptions for servicing income and costs and expected prepayment rates on the underlying loans. The estimated fair value is periodically evaluated for impairment by comparing actual cash flows and estimated future cash flows from the servicing assets to those estimated at the time the servicing assets were originated. Fair values are estimated using expected future discounted cash flows based on current market rates of interest. For purposes of measuring impairment, the servicing rights must be stratified by one or more predominant risk characteristics of the underlying loans. The Company stratifies its capitalized servicing rights based on product type and term of the underlying loans. The amount of impairment recognized is the amount, if any, by which the amortized cost of the servicing rights exceeds their fair value. Impairment, if deemed temporary, is recognized through a valuation allowance to the extent that fair value is less than the recorded amount.
Transfers of Financial Assets	Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity.
Income Taxes	The Company files a consolidated federal and various state income tax returns. The Bank provides for income taxes separately and remits to (receives from) Timberland Bancorp amounts currently due (receivable). Deferred income taxes result from temporary differences between the tax basis of assets and liabilities, and their reported amounts in the consolidated financial statements. These temporary differences will result in differences between income for tax purposes and income for financial reporting purposes in future years. As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. Valuation allowances are established to reduce the net recorded amount of deferred tax assets if it is determined to be more likely than not that all or some portion of the potential deferred tax asset will not be realized. With respect to accounting for uncertainty in incomes taxes, a tax provision is recognized as a benefit only if it is “more likely than not” that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50% likely to be realized upon examination. For tax positions not meeting the “more likely than not” test, no tax benefit is recorded. The Company recognizes interest and/or penalties related to income tax matters as income tax expense. The Company is no longer subject to U.S. federal income tax examination by tax authorities for years ended on or before September 30, 2016.
ESOP	The Bank sponsors a leveraged ESOP; however, all ESOP debt was fully repaid during the year ended September 30, 2019. The debt of the ESOP was payable to Timberland Bancorp, was recorded as other borrowed funds of the Bank, and was eliminated in the consolidated financial statements. The shares of the Company's common stock pledged as collateral for the ESOP's debt were reported as unearned shares issued to the ESOP in the consolidated financial statements. As shares were released from collateral, compensation expense was recorded equal to the average market price of the shares for the period, and the shares became available for net income per common share calculations. Dividends paid on unallocated shares reduced the Company’s cash contributions to the ESOP.
Advertising	Costs for advertising and marketing are expensed as incurred.
Stock-based Compensation	The Company measures compensation cost for all stock-based awards based on the grant-date fair value of the stock-based awards and recognizes compensation cost over the service period of stock-based awards. The fair value of stock options is determined using the Black-Scholes valuation model. Stock option forfeitures are accounted for as they occur.
Net Income Per Common Share	Basic net income per common share is computed by dividing net income to common shareholders by the weighted average number of common shares outstanding during the period, without considering any dilutive items. Diluted net income per common share is computed by dividing net income to common shareholders by the weighted average number of common shares and common stock equivalents for items that are dilutive, net of shares assumed to be repurchased using the treasury stock method at the average share price for the Company's common stock during the period. Common stock equivalents arise from the assumed conversion of outstanding stock options. Shares owned by the Bank’s ESOP that have not been allocated are not considered to be outstanding for the purpose of computing basic and diluted net income per common share.
Related Party Transactions	The Chairman of the Board of the Bank and Timberland Bancorp is a member of the law firm that provides general counsel to the Company.
Recent Accounting Pronouncements	In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, Revenue from Contracts with Customers, which created FASB Accounting Standards Codification ("ASC") Topic 606 ("ASC 606"). The core principle of ASC 606 is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following steps: (1) identify the contract(s) with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. ASC 606 was effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted ASC 606 on October 1, 2018 using the modified retrospective approach. Therefore, the comparative information has not been adjusted and continues to be reported under the superseded ASC 605. There was no cumulative effect adjustment as of October 1, 2018, and there were no material changes to the timing or amount of revenue recognized for the year ended September 30, 2019; however, additional disclosures were incorporated in the footnotes upon adoption. The majority of the Company's revenue is comprised of interest income from financial assets, which is explicitly excluded from the scope of ASC 606. The Company elected to apply the practical expedient pursuant to ASC 606 and therefore does not disclose information about remaining performance obligations that have an original expected term of one year or less and allows the Company to expense costs related to obtaining a contract as incurred when the amortization period would have been one year or less. See Note 24 for additional information. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 generally requires equity investments - except those accounted for under the equity method of accounting or those that result in consolidation of the investee - to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. ASU 2016-01 is intended to simplify the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment. ASU 2016-01 also eliminates certain disclosures related to the fair value of financial instruments and requires entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes. ASU 2016-01 was effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted ASU 2016-01 on October 1, 2018. As required by ASU 2016-01, on October 1, 2018 the Company recorded a one-time cumulative effect adjustment of $63,000 representing net unrealized losses on equity securities (mutual funds) between accumulated other comprehensive loss and retained earnings on the accompanying consolidated balance sheet. Additionally, the fair values of financial instruments for disclosure purposes were computed using an exit price notion and deposits with no stated maturity are no longer included in the fair value disclosures in Note 22. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which created FASB ASC Topic 842 ("ASC 842") and is intended to increase transparency and comparability among organizations by requiring the recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The principal change required by ASC 842 relates to lessee accounting, and is that for operating leases, a lessee is required to (1) recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, in the statement of financial position, (2) recognize a single lease cost, calculated so that the cost of the lease is allocated over the lease term generally on a straight-line basis, and (3) classify all cash payments within operating activities in the statement of cash flows. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it should recognize lease expense for such leases generally on a straight-line basis over the lease term. ASC 842 also changes disclosure requirements related to leasing activities and requires certain qualitative disclosures along with specific quantitative disclosures. ASC 842 also provides an optional transition method for adoption, under which an entity initially applies ASC 842 at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Consequently, an entity's reporting for the comparative periods presented in the financial statements in which it adopts ASC 842 will continue to be in accordance with current GAAP. ASC 842 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2018. Early application of ASC 842 is permitted. The Company adopted the provisions of ASC 842 effective October 1, 2019 utilizing the optional transition method and will not restate comparative periods. The Company also elected the package of practical expedients permitted under ASC 842's transition guidance, which allows the Company to carryforward its historical lease classifications and its assessment as to whether a contract is or contains a lease. The Company also elected to not recognize lease assets and lease liabilities for leases with an initial term of 12 months or less. As a result of adopting ASC 842, ROU assets and operating lease liabilities increased by $2.89 million on October 1, 2019. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses, as amended by ASU 2018-19, ASU 2019-04 and ASU 2019-05. This ASU replaces the existing incurred losses methodology with a current expected losses methodology with respect to most financial assets measured at amortized cost and certain other instruments, including trade and other receivables, loans, held to maturity investment securities and off-balance sheet commitments. In addition, this ASU requires credit losses relating to available for sale debt securities to be recorded through an allowance for credit losses rather than as a reduction of the carrying amount. ASU 2016-13 also changes the accounting for purchased credit-impaired debt securities and loans. ASU 2016-13 retains many of the current disclosure requirements in GAAP and expands certain disclosure requirements. ASU 2016-13 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Upon adoption, the Company expects a change in the processes and procedures to calculate the allowance for loan losses, including changes in the assumptions and estimates to consider expected credit losses over the life of the loan versus the current accounting practice that utilizes the incurred loss model. In addition, the current policy for other-than-temporary impairment on investment securities available for sale will be replaced with an allowance approach. The Company is reviewing the requirements of ASU 2016-13 and has begun developing and implementing processes and procedures to ensure it is fully compliant with the amendments at the adoption date. At this time, the Company anticipates the allowance for loan losses will increase as a result of the implementation of this ASU; however, until its evaluation is complete, the magnitude of the increase will be unknown. In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other: Simplifying the Test for Goodwill Impairment. This ASU simplifies the subsequent measurement of goodwill and eliminates Step 2 from the goodwill impairment test. In computing the implied fair value of goodwill under Step 2, an entity had to perform procedures to determine the fair value of its assets and liabilities (including unrecognized assets and liabilities) at the impairment testing date following the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. Under ASU 2017-04, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit's fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. ASU 2017-04 is effective for annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2022. The adoption ASU 2017-04 is not expected to a have a material impact on the Company's future consolidated financial statements. In March 2017, the FASB issued ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. This ASU shortens the amortization period for certain callable debt securities held at a premium to the earliest call date. This ASU was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2018. The Company adopted ASU 2017-08 effective October 1, 2019 and it did not have a material impact on the Company's consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting. This ASU was issued to provide clarity as to when to apply modification accounting when there is a change in the terms or conditions of a share-based payment award. According to the ASU, an entity should account for the effects of a modification unless the fair value, vesting conditions, and balance sheet classification of the award are the same after the modification as compared to the original award prior to modification. ASU 2017-09 was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2017, with early adoption permitted. The Company adopted ASU 2017-09 effective October 1, 2018 and it did not have a material impact on the Company's consolidated financial statements. In June 2018, the FASB issued ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This ASU was issued to expand the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. Previously, these awards were recorded at the fair value of consideration received or the fair value of the equity instruments issued and were measured at the earlier of the commitment date or the date performance was completed. The amendments in this ASU require nonemployee share-based payment awards to be measured at the grant-date fair value of the equity instrument. ASU 2018-07 was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2018. The Company adopted ASU 2018-07 effective October 1, 2019 and it did not have a material impact on the Company's consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement. This ASU modifies the disclosure requirements for fair value measurements. The following disclosure requirements were removed from ASC Topic 820, Fair Value Measurement: (1) the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; (2) the policy for timing of transfers between levels; and (3) the valuation process for Level 3 fair value measurements. This ASU clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. This ASU adds the following disclosure requirements for Level 3 measurements: (1) changes in unrealized gains and losses for the period included in other comprehensive income for the recurring Level 3 fair value measurements held at the end of the reporting period, and (2) the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. ASU 2018-13 was effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted ASU 2018-13 effective October 1, 2020 and it is not expected to have a material impact on the Company's future consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40), Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The amendments in this ASU broaden the scope of ASC Subtopic 350-40 to include costs incurred to implement a hosting arrangement that is a service contract. The amendments align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The costs are capitalized or expensed depending on the nature of the costs and the project stage during which they are incurred, consistent with the accounting for internal-use software costs. The amendments in this ASU result in consistent capitalization of implementation costs of a hosting arrangement that is a service contract and implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this ASU. ASU 2018-15 was effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted ASU 2018-15 effective October 1, 2020 and it is not expected to have a material impact on the Company's future consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740), Simplifying the accounting for Income Taxes. The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments also improve consistent application of and simplify GAAP for other areas of Topic 740 by clarifying and amending existing guidelines. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021, including interim periods within fiscal years. The adoption of ASU 2019-12 is not expected to have a material impact on the Company's future consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. This ASU applies to contracts, hedging relationships and other transactions that reference the London Interbank Offered Rate ("LIBOR") or other rate references expected to be discontinued because of reference rate reform. The ASU permits an entity to make necessary modifications to eligible contracts or transactions without requiring contract remeasurement or reassessment of a previous accounting determination. This ASU is effective for all entities as of March 12, 2020 through December 31, 2022. The Company has not adopted ASU 2020-04 as of September 30, 2020. The adoption of ASU 2020-04 is not expected to have a material impact on the Company's future consolidated financial statements. On March 22, 2020, federal banking regulators issued an interagency statement that included guidance on their approach for the accounting of loan modifications in light of the economic impact of the COVID-19 pandemic. The guidance interprets current accounting standards and indicates that a lender can conclude that a borrower is not experiencing financial difficulty if short-term modifications are made in response to COVID-19, such as payment deferrals, fee waivers, extensions of repayment terms, or other delays in payment that are insignificant related to the loans in which the borrower is less than 30 days past due on its contractual payments at the time a modification is implemented. The agencies confirmed in working with the staff of the FASB that short-term modification made on a good faith basis in response to COVID-19 to borrowers who were current prior to any relief are not troubled debt restructurings.

Summary of Significant Accounting Policies: Basis of Presentation (Policies)

12 Months Ended

Sep. 30, 2020

The accompanying consolidated financial statements include the accounts of Timberland Bancorp, Inc. (“Timberland Bancorp”); its wholly owned subsidiary, Timberland Bank (the “Bank”); and the Bank’s wholly owned subsidiary, Timberland Service Corp. (collectively, the "Company”). All significant intercompany transactions and balances have been eliminated in consolidation.

Nature of Operations

Timberland Bancorp is a bank holding company which operates primarily through its subsidiary, the Bank. The Bank was established in 1915 and, through its 24 branches located in Grays Harbor, Pierce, Thurston, Kitsap, King and Lewis counties in Washington State, attracts deposits from the general public, and uses those funds, along with other borrowings, primarily to provide residential real estate, construction, commercial real estate, commercial business and consumer loans to borrowers primarily in western Washington.

Consolidated Financial Statement Presentation

The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S.") (“GAAP”) and prevailing practices within the banking industry.

Use of Estimates

The preparation of consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities, as of the date of the consolidated balance sheets, and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term relate to the determination of the allowance for loan losses, the determination of any OTTI in the fair value of investment securities, the valuation of servicing rights, the valuation of OREO, the valuation of assets acquired and liabilities assumed in acquisitions and the valuation of goodwill for potential impairment.

Reclassification Policy

Certain prior year amounts have been reclassified to conform to the 2020 fiscal year presentation with no change to previously reported net income or shareholders’ equity.

Segment Reporting

The Company has one reportable operating segment which is defined as community banking in western Washington under the operating name “Timberland Bank.”

Cash and Cash Equivalents and Cash Flows

The Company considers amounts included in the consolidated balance sheets’ captions “Cash and due from financial institutions” and “Interest-bearing deposits in banks,” all of which mature within ninety days, to be cash equivalents for purposes of reporting cash flows.

CDs Held for Investment

CDs held for investment include amounts invested with other FDIC-insured financial institutions for a stated interest rate and with a fixed maturity date. Such CDs generally have maturities of 12 to 60 months from the date of purchase by the Company. Early withdrawal penalties may apply; however, the Company intends to hold these CDs to maturity. The Company generally limits its purchases of CDs to a maximum of $250,000 (the FDIC insurance coverage limit) with any single financial institution.

Investment Securities

Investments in debt securities are classified upon acquisition as held to maturity or available for sale. Investments in debt securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and reported at amortized cost. Investments in debt securities classified as available for sale are reported at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income (loss), net of income tax effects. Premiums and discounts are amortized to interest income using the interest method over the contractual lives of the securities. Gains and losses on sales of investment securities are recognized on the trade date and determined using the specific identification method.

In estimating whether there are any OTTI losses, management considers (1) the length of time and the extent to which the fair value has been less than amortized cost, (2) the financial condition and near term prospects of the issuer, (3) the impact of changes in market interest rates and (4) the intent and ability of the Company to retain its investment for a period of time sufficient to allow for any anticipated recovery in fair value.

Declines in the fair value of individual debt securities available for sale that are deemed to be other than temporary are recognized in earnings when identified. The fair value of the debt security then becomes the new cost basis. For individual debt securities that are held to maturity which the Company does not intend to sell, and it is not more likely than not that the Company will be required to sell before recovery of its amortized cost basis, the other than temporary decline in the fair value of the debt security related to: (1) credit loss is recognized in earnings and (2) market or other factors is recognized in other comprehensive income (loss). Credit loss is recorded if the present value of expected future cash flows is less than the amortized cost. For individual debt securities which the Company intends to sell or more likely than not will not recover all of its amortized cost, the OTTI is recognized in earnings equal to the entire difference between the debt security’s cost basis and its fair value at the consolidated balance sheet date. For individual debt securities for which credit loss has been recognized in earnings, interest accruals and amortization and accretion of premiums and discounts are suspended when the credit loss is recognized. Interest received after accruals have been suspended is recognized on a cash basis.

FHLB Stock

The Bank, as a member of the FHLB, is required to maintain an investment in capital stock of the FHLB in an amount equal to 0.12% of the Bank's total assets plus 4.00% of any borrowings from the FHLB. No ready market exists for this stock, and it has no quoted market value. However, redemption of FHLB stock has historically been at par value. The Company's investment in FHLB stock is carried at cost, which approximates fair value.

The Company evaluates its FHLB stock for impairment as needed. The Company's determination of whether this investment is impaired is based on its assessment of the ultimate recoverability of cost rather than by recognizing temporary declines in value. The determination of whether a decline affects the ultimate recoverability of cost is influenced by criteria such as (1) the significance of any decline in net assets of the FHLB as compared with the capital stock amount and the length of time any decline has persisted; (2) commitments by the FHLB to make payments required by law or regulation and the level of such payments in relation to the operating performance of the FHLB; (3) the impact of legislative and regulatory changes on

institutions and, accordingly, the customer base of the FHLB; and (4) the liquidity position of the FHLB. Based on its evaluation, the Company determined that there was no impairment of FHLB stock at September 30, 2020 and 2019.

Loans Held for Sale

Mortgage loans and commercial business loans originated and intended for sale in the secondary market are stated in the aggregate at the lower of cost or estimated fair value. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. Gains or losses on sales of loans are recognized at the time of sale. The gain or loss is the difference between the net sales proceeds and the recorded value of the loans, including any remaining unamortized deferred loan origination fees.

Loans Receivable

Loans are stated at the amount of unpaid principal, reduced by the undisbursed portion of construction loans in process, net deferred loan origination fees and the allowance for loan losses.

Interest on Loans, Non-accrual Loans and Loan Fees

Interest on loans is accrued daily based on the principal amount outstanding. Generally, the accrual of interest on loans is discontinued when, in management’s opinion, the borrower may be unable to make payments as they become due or when they are past due 90 days as to either principal or interest (based on contractual terms), unless the loan is well secured and in the process of collection. In determining whether a borrower may be able to make payments as they become due, management considers circumstances such as the financial strength of the borrower, the estimated collateral value, reasons for the delays in payments, payment record, the amounts past due and the number of days past due. All interest accrued but not collected for loans that are placed on non-accrual status or charged off is reversed against interest income. Subsequent collections on a cash basis are applied proportionately to past due principal and interest, unless collectability of principal is in doubt, in which case all payments are applied to principal. Loans are returned to accrual status when the loan is deemed current, and the collectability of principal and interest is no longer doubtful, or, in the case of one- to four-family loans, when the loan is less than 90 days delinquent. The categories of non-accrual loans and impaired loans overlap, although they are not identical.

The Company charges fees for originating loans. These fees, net of certain loan origination costs, are deferred and amortized to income on the level-yield basis over the loan term. If the loan is repaid prior to maturity, the remaining unamortized deferred loan origination fee is recognized in income at the time of repayment.

Troubled Debt Restructured Loans

A troubled debt restructured loan ("TDR") is a loan for which the Company, for reasons related to a borrower’s financial difficulties, grants a concession to the borrower that the Company would not otherwise consider. Examples of such concessions include, but are not limited to: a reduction in the stated interest rate; an extension of the maturity at an interest rate below current market rates; a reduction in the face amount of the debt; a reduction in the accrued interest; or re-amortizations, extensions, deferrals and renewals. TDRs are considered impaired and are individually evaluated for impairment. TDRs are classified as non-accrual (and considered to be non-performing) unless they have been performing in accordance with modified terms for a period of at least six months. In March 2020, the Company announced loan modification programs to support and provide relief for its borrowers during the novel coronavirus of 2019 ("COVID-19") pandemic. The Company has followed the loan modification criteria within the Coronavirus Aid, Relief, and Economic Security Act of 2020 ("CARES Act"), which was signed into law on March 27, 2020 and interagency guidance from the federal banking agencies when determining if a borrower's modification is subject to a TDR classification. If it is determined that the modification does not meet the criteria under the CARES Act or interagency guidance to be excluded from TDR classification, the Company evaluates the loan modifications under its existing TDR framework. Loans subject to forbearance under the COVID-19 loan modification program are not reported as past due or placed on non-accrual status during the forbearance time period, and interest income continues to be recognized over the contractual life of the loans.

Allowance for Loan Losses

The allowance for loan losses is maintained at a level sufficient to provide for probable losses inherent in the loan portfolio. The allowance is provided based upon management's comprehensive analysis of the pertinent factors underlying the quality of the loan portfolio. These factors include changes in the amount and composition of the loan portfolio, delinquency levels, actual loan loss experience, current economic conditions, and a detailed analysis of individual loans for which full collectability may not be assured. The detailed analysis includes methods to estimate the fair value of loan collateral and the existence of potential alternative sources of repayment. The allowance consists of specific and general components. The specific component relates to loans that are deemed impaired. For loans that are classified as impaired, an allowance is established when the discounted cash flows, collateral value less selling costs (if applicable), or observable market price of the impaired loan is lower than the recorded value of that loan. The general component covers non-impaired loans and is based on historical loss experience adjusted for qualitative factors. The Company's historical loss experience is determined by evaluating the average net charge-offs over the most recent economic cycle, but not to exceed six years. Qualitative factors are determined by loan type and allow management to adjust reserve levels to reflect the current general economic environment and portfolio performance trends including recent charge-off trends. Allowances are provided based on management’s continuing evaluation of the pertinent factors underlying the quality of the loan portfolio, including changes in the size and composition of the loan portfolio, actual loan loss experience, current economic conditions, collateral values, geographic concentrations, seasoning of the loan portfolio, specific industry conditions, the duration of the current business cycle, and regulatory requirements and expectations. When determining the appropriate historical loss and qualitative factors, management took into consideration the impact of the COVID-19 pandemic on such factors as the national and state unemployment rates and related trends, the amount of and timing of financial assistance provided by the government, consumer spending levels and trends, industries significantly impacted by the COVID-19 pandemic, and the Company's COVID-19 loan modification program. The appropriateness of the allowance for loan losses is estimated based upon these factors and trends identified by management at the time the consolidated financial statements are prepared.

A loan is considered impaired when it is probable that the Company will be unable to collect all amounts (principal and interest) when due according to the contractual terms of the loan agreement. Smaller balance homogeneous loans, such as residential mortgage loans and consumer loans, may be collectively evaluated for impairment. When a loan has been identified as being impaired, the amount of the impairment is measured by using discounted cash flows, except when, as an alternative, the current estimated fair value of the collateral (reduced by estimated costs to sell, if applicable) or observable market price is used. The valuation of real estate collateral is subjective in nature and may be adjusted in future periods because of changes in economic conditions. Management considers third-party appraisals, as well as independent fair market value assessments from realtors or persons involved in selling real estate, in determining the estimated fair value of particular properties. In addition, as certain of

these third-party appraisals and independent fair market value assessments are only updated periodically, changes in the values of specific properties may have occurred subsequent to the most recent appraisals. Accordingly, the amounts of any such potential changes and any related adjustments are generally recorded at the time such information is received. When the estimated net realizable value of the impaired loan is less than the recorded investment in the loan (including accrued interest

and net deferred loan origination fees or costs), impairment is recognized by creating or adjusting an allocation of the allowance for loan losses and uncollected accrued interest is reversed against interest income. If ultimate collection of principal is in doubt, all cash receipts on impaired loans are applied to reduce the principal balance.

A provision for (recapture of) loan losses is charged (credited) to operations and is added to (deducted from) the allowance for loan losses based on a quarterly comprehensive analysis of the loan portfolio. The allowance for loan losses is allocated to

certain loan categories based on the relative risk characteristics, asset classifications and actual loss experience of the loan portfolio. While management has allocated the allowance for loan losses to various loan portfolio segments, the allowance is general in nature and is available for the loan portfolio in its entirety.

The ultimate recovery of all loans is susceptible to future market factors beyond the Company’s control. These factors may result in losses or recoveries differing significantly from those provided in the consolidated financial statements. If real estate values decline and as updated appraisals are received on collateral for impaired loans, the Company may need to increase the allowance for loan losses appropriately. In addition, regulatory agencies, as an integral part of their examination process, periodically review the Company’s allowance for loan losses, and may require the Company to make additions to the allowance based on their judgment about information available to them at the time of their examinations.

Premises and Equipment

Premises and equipment are recorded at cost. Depreciation is computed using the straight-line method over the following estimated useful lives: buildings and improvements - five to 40 years and furniture and equipment - three to seven years. The cost of maintenance and repairs is charged to expense as incurred. Gains and losses on dispositions are reflected in earnings.

Impairment of Long-Lived Assets

Long-lived assets, consisting of premises and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the recorded amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the recorded amount of an asset to undiscounted future net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the recorded amount of the assets exceeds the discounted recovery amount or estimated fair value of the assets. No events or changes in circumstances have occurred during the years ended September 30, 2020 or 2019 that would cause management to evaluate the recoverability of the Company’s long-lived assets.

OREO and Other Repossessed Assets

OREO and other repossessed assets consist of properties or assets acquired through or in lieu of foreclosure, and are recorded initially at the estimated fair value of the properties less estimated costs of disposal, establishing a new cost basis. These assets are subsequently accounted for at lower of cost or fair value less estimated costs to sell. When the property is acquired, any excess of the loan balance over the estimated net realizable value is charged to the allowance for loan losses. The valuation of real estate is subjective in nature and may be adjusted in future periods because of changes in economic conditions. Management considers third-party appraisals, as well as independent fair market value assessments from realtors or persons involved in selling real estate, in determining the estimated fair values of particular properties. In addition, as certain of these third-party appraisals and independent fair market value assessments are only updated periodically, changes in the values of specific properties may have occurred subsequent to the most recent appraisals. Accordingly, the amounts of any such potential changes and any related adjustments are generally recorded at the time such information is received.

BOLI

BOLI policies are recorded at their cash surrender value less applicable cash surrender charges. Income from BOLI is recognized when earned.

Goodwill

Goodwill is initially recorded when the purchase price paid in a business combination exceeds the estimated fair value of the net identified tangible and intangible assets acquired and liabilities assumed. Goodwill is presumed to have an indefinite useful life and is analyzed annually for impairment. The Company performs an annual review during the third quarter of each fiscal year, or more frequently if indicators of potential impairment exist, to determine if the recorded goodwill is impaired. For purposes of goodwill impairment testing, the services offered through the Bank and its subsidiary are managed as one strategic unit and represent the Company's only reporting unit.

The annual goodwill impairment test begins with a qualitative assessment of whether it is "more likely than not" that the reporting unit's fair value is less than its carrying amount. If an entity concludes that it is not "more likely than not" that the fair value of a reporting unit is less than its carrying amount, it need not perform a two-step impairment test. If the Company's qualitative assessment concluded that it is "more likely than not" that the fair value of its reporting unit is less than its carrying amount, it must perform the two-step impairment test to identify potential goodwill impairment and measure the amount of goodwill impairment loss to be recognized, if any. The first step of the goodwill impairment test compares the estimated fair value of the reporting unit with its carrying amount, or the book value, including goodwill. If the estimated fair value of the reporting unit equals or exceeds its book value, goodwill is considered not impaired, and the second step of the impairment test is unnecessary.

The second step, if necessary, measures the amount of goodwill impairment loss to be recognized. The reporting unit must determine fair value for all assets and liabilities, excluding goodwill. The net of the assigned fair value of assets and liabilities is then compared to the book value of the reporting unit, and any excess book value becomes the implied fair value of goodwill. If the carrying amount of the goodwill exceeds the newly calculated implied fair value of goodwill, an impairment loss is recognized in the amount required to write-down the goodwill to the implied fair value.

Management's qualitative assessment takes into consideration macroeconomic conditions, industry and market considerations, cost or margin factors, financial performance and the share price of the Company's common stock. The Company performed its fiscal year 2020 goodwill impairment test during the quarter ended June 30, 2020 with the assistance of an independent third-party firm specializing in goodwill impairment valuations for financial institutions. The third-party analysis was conducted as of May 31, 2020 and the step one test concluded that the reporting unit's fair value was more than its recorded value and, therefore, step two of the analysis was not necessary. Accordingly, the recorded value of goodwill as of May 31, 2020 was not impaired.

A significant amount of judgment is involved in determining if an indicator of goodwill impairment has occurred. Such indicators may include, among others: a significant decline in expected future cash flows; a sustained, significant decline in the Company's stock price and market capitalization; a significant adverse change in legal factors or in the business climate; adverse assessment or action by a regulator; and unanticipated competition. Any change in these indicators could have a significant negative impact on the Company's financial condition, impact the goodwill impairment analysis or cause the Company to perform a goodwill impairment analysis more frequently than once per year.

As of September 30, 2020, management believes that there were no events or changes in the circumstances since May 31, 2020 that would indicate a potential impairment of goodwill. No assurances can be given, however, that the Company will not record an impairment loss on goodwill in the future. If adverse economic conditions or the recent decrease in the Company's stock price and market capitalization as a result of the COVID-19 pandemic were deemed to be other than temporary, it may significantly affect the fair value of the Company's goodwill and may trigger impairment charges. Any impairment charge could have a material adverse effect on the Company's results of operation and financial condition.

MSRs

The Company holds rights to service (1) loans that it has originated and sold to the Federal Home Loan Mortgage Corporation (“Freddie Mac”) and (2) the guaranteed portion of U.S. Small Business Administration ("SBA") loans sold in the secondary market. Servicing rights are capitalized at estimated fair value when acquired through the origination of loans that are subsequently sold with the servicing rights retained. Servicing rights are amortized to servicing income on loans sold approximately in proportion to and over the period of estimated net servicing income. The value of servicing rights at the date of the sale of loans is estimated based on the discounted present value of expected future cash flows using key assumptions for servicing income and costs and expected prepayment rates on the underlying loans. The estimated fair value is periodically evaluated for impairment by comparing actual cash flows and estimated future cash flows from the servicing assets to those estimated at the time the servicing assets were originated. Fair values are estimated using expected future discounted cash flows based on current market rates of interest. For purposes of measuring impairment, the servicing rights must be stratified by one or more predominant risk characteristics of the underlying loans. The Company stratifies its capitalized servicing rights based on product type and term of the underlying loans. The amount of impairment recognized is the amount, if any, by which the amortized cost of the servicing rights exceeds their fair value. Impairment, if deemed temporary, is recognized through a valuation allowance to the extent that fair value is less than the recorded amount.

Transfers of Financial Assets

Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity.

Income Taxes

The Company files a consolidated federal and various state income tax returns. The Bank provides for income taxes separately and remits to (receives from) Timberland Bancorp amounts currently due (receivable).

Deferred income taxes result from temporary differences between the tax basis of assets and liabilities, and their reported amounts in the consolidated financial statements. These temporary differences will result in differences between income for tax purposes and income for financial reporting purposes in future years. As changes in tax laws or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. Valuation allowances are established to reduce the net recorded amount of deferred tax assets if it is determined to be more likely than not that all or some portion of the potential deferred tax asset will not be realized.

With respect to accounting for uncertainty in incomes taxes, a tax provision is recognized as a benefit only if it is “more likely than not” that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50% likely to be realized upon examination. For tax positions not meeting the “more likely than not” test, no tax benefit is recorded. The Company recognizes interest and/or penalties related to income tax matters as income tax expense. The Company is no longer subject to U.S. federal income tax examination by tax authorities for years ended on or before September 30, 2016.

ESOP

The Bank sponsors a leveraged ESOP; however, all ESOP debt was fully repaid during the year ended September 30, 2019. The debt of the ESOP was payable to Timberland Bancorp, was recorded as other borrowed funds of the Bank, and was eliminated in the consolidated financial statements. The shares of the Company's common stock pledged as collateral for the ESOP's debt were reported as unearned shares issued to the ESOP in the consolidated financial statements. As shares were released from collateral, compensation expense was recorded equal to the average market price of the shares for the period, and the shares became available for net income per common share calculations. Dividends paid on unallocated shares reduced the Company’s cash contributions to the ESOP.

Advertising

Costs for advertising and marketing are expensed as incurred.

Stock-based Compensation

The Company measures compensation cost for all stock-based awards based on the grant-date fair value of the stock-based awards and recognizes compensation cost over the service period of stock-based awards. The fair value of stock options is determined using the Black-Scholes valuation model. Stock option forfeitures are accounted for as they occur.

Net Income Per Common Share

Basic net income per common share is computed by dividing net income to common shareholders by the weighted average number of common shares outstanding during the period, without considering any dilutive items. Diluted net income per common share is computed by dividing net income to common shareholders by the weighted average number of common shares and common stock equivalents for items that are dilutive, net of shares assumed to be repurchased using the treasury stock method at the average share price for the Company's common stock during the period. Common stock equivalents arise from the assumed conversion of outstanding stock options. Shares owned by the Bank’s ESOP that have not been allocated are not considered to be outstanding for the purpose of computing basic and diluted net income per common share.

Related Party Transactions

The Chairman of the Board of the Bank and Timberland Bancorp is a member of the law firm that provides general counsel to the Company.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, Revenue from Contracts with Customers, which created FASB Accounting Standards Codification ("ASC") Topic 606 ("ASC 606"). The core principle of ASC 606 is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following steps: (1) identify the contract(s) with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. ASC 606 was effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted ASC 606 on October 1, 2018 using the modified retrospective approach. Therefore, the comparative information has not been adjusted and continues to be reported under the superseded ASC 605. There was no cumulative effect adjustment as of October 1, 2018, and there were no material changes to the timing or amount of revenue recognized for the year ended September 30, 2019; however, additional disclosures were incorporated in the footnotes upon adoption. The majority of the Company's revenue is comprised of interest income from financial assets, which is explicitly excluded from the scope of ASC 606. The Company elected to apply the practical expedient pursuant to ASC 606 and therefore does not disclose information about remaining performance obligations that have an original expected term of one year or less and allows the Company to expense costs related to obtaining a contract as incurred when the amortization period would have been one year or less. See Note 24 for additional information.

In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 generally requires equity investments - except those accounted for under the equity method of accounting or those that result in consolidation of the investee - to be measured at fair value with changes in fair value recognized in net income. However, an entity may choose to measure equity investments that do not have readily determinable fair values at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. ASU 2016-01 is intended to simplify the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment. ASU 2016-01 also eliminates certain disclosures related to the fair value of financial instruments and requires entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes. ASU 2016-01 was effective for fiscal years beginning after December 15, 2017, including interim periods

within those fiscal years. The Company adopted ASU 2016-01 on October 1, 2018. As required by ASU 2016-01, on October 1, 2018 the Company recorded a one-time cumulative effect adjustment of $63,000 representing net unrealized losses on equity securities (mutual funds) between accumulated other comprehensive loss and retained earnings on the accompanying consolidated balance sheet. Additionally, the fair values of financial instruments for disclosure purposes were computed using an exit price notion and deposits with no stated maturity are no longer included in the fair value disclosures in Note 22.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which created FASB ASC Topic 842 ("ASC 842") and is intended to increase transparency and comparability among organizations by requiring the recognition of lease assets and lease liabilities on the balance sheet and disclosure of key information about leasing arrangements. The principal change required by ASC 842 relates to lessee accounting, and is that for operating leases, a lessee is required to (1) recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, in the statement of financial position, (2) recognize a single lease cost, calculated so that the cost of the lease is allocated over the lease term generally on a straight-line basis, and (3) classify all cash payments within operating activities in the statement of cash flows. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. If a lessee makes this election, it should recognize lease expense for such leases generally on a straight-line basis over the lease term. ASC 842 also changes disclosure requirements related to leasing activities and requires certain qualitative disclosures along with specific quantitative disclosures. ASC 842 also provides an optional transition method for adoption, under which an entity initially applies ASC 842 at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Consequently, an entity's reporting for the comparative periods presented in the financial statements in which it adopts ASC 842 will continue to be in accordance with current GAAP. ASC 842 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2018. Early application of ASC 842 is permitted. The Company adopted the provisions of ASC 842 effective October 1, 2019 utilizing the optional transition method and will not restate comparative periods. The Company also elected the package of practical expedients permitted under ASC 842's transition guidance, which allows the Company to carryforward its historical lease classifications and its assessment as to whether a contract is or contains a lease. The Company also elected to not recognize lease assets and lease liabilities for leases with an initial term of 12 months or less. As a result of adopting ASC 842, ROU assets and operating lease liabilities increased by $2.89 million on October 1, 2019.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses, as amended by ASU 2018-19, ASU 2019-04 and ASU 2019-05. This ASU replaces the existing incurred losses methodology with a current expected losses methodology with respect to most financial assets measured at amortized cost and certain other instruments, including trade and other receivables, loans, held to maturity investment securities and off-balance sheet commitments. In addition, this ASU requires credit losses relating to available for sale debt securities to be recorded through an allowance for credit losses rather than as a reduction of the carrying amount. ASU 2016-13 also changes the accounting for purchased credit-impaired debt securities and loans. ASU 2016-13 retains many of the current disclosure requirements in GAAP and expands certain disclosure requirements. ASU 2016-13 is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Upon adoption, the Company expects a change in the processes and procedures to calculate the allowance for loan losses, including changes in the assumptions and estimates to consider expected credit losses over the life of the loan versus the current accounting practice that utilizes the incurred loss model. In addition, the current policy for other-than-temporary impairment on investment securities available for sale will be replaced with an allowance approach. The Company is reviewing the requirements of ASU 2016-13 and has begun developing and implementing processes and procedures to ensure it is fully compliant with the amendments at the adoption date. At this time, the Company anticipates the allowance for loan losses will increase as a result of the implementation of this ASU; however, until its evaluation is complete, the magnitude of the increase will be unknown.

In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other: Simplifying the Test for Goodwill Impairment. This ASU simplifies the subsequent measurement of goodwill and eliminates Step 2 from the goodwill impairment test. In computing the implied fair value of goodwill under Step 2, an entity had to perform procedures to determine the fair value of its assets and liabilities (including unrecognized assets and liabilities) at the impairment testing date following the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. Under ASU 2017-04, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by

which the carrying amount exceeds the reporting unit's fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, an entity should consider income tax effects from any tax

deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. ASU 2017-04 is effective for annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2022.

The adoption ASU 2017-04 is not expected to a have a material impact on the Company's future consolidated financial statements.

In March 2017, the FASB issued ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. This ASU shortens the amortization period for certain callable debt securities held at a premium to the earliest call date. This ASU was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2018. The Company adopted ASU 2017-08 effective October 1, 2019 and it did not have a material impact on the Company's consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting. This ASU was issued to provide clarity as to when to apply modification accounting when there is a change in the terms or conditions of a share-based payment award. According to the ASU, an entity should account for the effects of a modification unless the fair value, vesting conditions, and balance sheet classification of the award are the same after the modification as compared to the original award prior to modification. ASU 2017-09 was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2017, with early adoption permitted. The Company adopted ASU 2017-09 effective October 1, 2018 and it did not have a material impact on the Company's consolidated financial statements.

In June 2018, the FASB issued ASU 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This ASU was issued to expand the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. Previously, these awards were recorded at the fair value of consideration received or the fair value of the equity instruments issued and were measured at the earlier of the commitment date or the date performance was completed. The amendments in this ASU require nonemployee share-based payment awards to be measured at the grant-date fair value of the equity instrument. ASU 2018-07 was effective for fiscal years, including interim periods within those fiscal years, beginning after December 15, 2018. The Company adopted ASU 2018-07 effective October 1, 2019 and it did not have a material impact on the Company's consolidated financial statements.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement. This ASU modifies the disclosure requirements for fair value measurements. The following disclosure requirements were removed from ASC Topic 820, Fair Value Measurement: (1) the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy; (2) the policy for timing of transfers between levels; and (3) the valuation process for Level 3 fair value measurements. This ASU clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. This ASU adds the following disclosure requirements for Level 3 measurements: (1) changes in unrealized gains and losses for the period included in other comprehensive income for the recurring Level 3 fair value measurements held at the end of the reporting period, and (2) the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. ASU 2018-13 was effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted ASU 2018-13 effective October 1, 2020 and it is not expected to have a material impact on the Company's future consolidated financial statements.

In August 2018, the FASB issued ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40), Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The amendments in this ASU broaden the scope of ASC Subtopic 350-40 to include costs incurred to implement a hosting arrangement that is a service contract. The amendments align the requirements for capitalizing implementation costs incurred

in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The costs are capitalized or expensed depending on the nature of the costs and the project stage during which they are incurred, consistent with the accounting for internal-use software costs. The amendments in this ASU result in consistent capitalization of implementation costs of a hosting arrangement that is a service contract and implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this ASU. ASU 2018-15 was effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company adopted ASU 2018-15 effective October 1, 2020 and it is not expected to have a material impact on the Company's future consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740), Simplifying the accounting for Income Taxes. The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments also improve consistent application of and simplify GAAP for other areas of Topic 740 by clarifying and amending existing guidelines. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021,

including interim periods within fiscal years. The adoption of ASU 2019-12 is not expected to have a material impact on the Company's future consolidated financial statements.

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. This ASU applies to contracts, hedging relationships and other transactions that reference the London Interbank Offered Rate ("LIBOR") or other rate references expected to be discontinued because of reference rate reform. The ASU permits an entity to make necessary modifications to eligible contracts or transactions without requiring contract remeasurement or reassessment of a previous accounting determination. This ASU is effective for all entities as of March 12, 2020 through December 31, 2022. The Company has not adopted ASU 2020-04 as of September 30, 2020. The adoption of ASU 2020-04 is not expected to have a material impact on the Company's future consolidated financial statements.

On March 22, 2020, federal banking regulators issued an interagency statement that included guidance on their approach for the accounting of loan modifications in light of the economic impact of the COVID-19 pandemic. The guidance interprets current accounting standards and indicates that a lender can conclude that a borrower is not experiencing financial difficulty if short-term modifications are made in response to COVID-19, such as payment deferrals, fee waivers, extensions of repayment terms, or other delays in payment that are insignificant related to the loans in which the borrower is less than 30 days past due on its contractual payments at the time a modification is implemented. The agencies confirmed in working with the staff of the FASB that short-term modification made on a good faith basis in response to COVID-19 to borrowers who were current prior to any relief are not troubled debt restructurings.