497

February 18, 2016

VIA EDGAR

Securities and Exchange Commission

Investment Company Division

100 F. Street, N.E.

Washington, DC 20549

Attention: Office of Filings, Information & Consumer Services

RE:	Wasatch Funds Trust (the “Trust”)
	File Nos. 33-010451, 811-04920

To the Commission:

The Supplement is being filed to submit exhibits containing interactive data format risk/return summary information that mirrors the risk/return summary information in the Prospectus dated January 31, 2016 for the Investor Class shares of the Wasatch Micro Cap Fund and Wasatch Micro Cap Value Fund, as filed electronically via EDGAR with the Securities and Exchange Commission on February 1, 2016 (Accession Number: 0001193125-16-445315).

If you have any questions concerning this filing, you may contact me at (617) 662-3969.

Very truly yours,

/s/ Francine S. Hayes

Francine S. Hayes

Vice President and Senior Counsel

cc: R. Biles

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	Other
Document Period End Date	dei_DocumentPeriodEndDate	Sep. 30, 2015
Registrant Name	dei_EntityRegistrantName	WASATCH FUNDS TRUST
Central Index Key	dei_EntityCentralIndexKey	0000806633
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Feb. 01, 2016
Document Effective Date	dei_DocumentEffectiveDate	Feb. 01, 2016
Prospectus Date	rr_ProspectusDate	Jan. 31, 2016

XML

Wasatch Micro Cap Fund

WASATCH MICRO CAP FUND® — SUMMARY

INVESTMENT OBJECTIVE

The Fund’s primary investment objective is long-term growth of capital.

Income is a secondary objective, but only when consistent with long-term growth of capital. Currently, we do not expect the Fund’s investments to generate substantial income.

FEES AND EXPENSES OF THE FUND

The tables below describe the fees and expenses that you may pay if you buy, sell or hold Investor Class shares of the Fund.

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)

Shareholder Fees	Wasatch Micro Cap Fund Investor Class Shares
Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)	none
Redemption Fee (as a % of amount redeemed on shares held 60 days or less)	2.00%
Exchange Fee	none
Maximum Account Fee	none

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT YOU PAY EACH YEAR AS A PERCENTAGE OF THE VALUE OF YOUR INVESTMENT)

Annual Fund Operating Expenses	Wasatch Micro Cap Fund Investor Class Shares
Management Fee	1.75%
Distribution/Service (12b-1) Fee	none
Other Expenses	0.15%
Total Annual Fund Operating Expenses	1.90%	[1]

EXAMPLE

This example is intended to help you compare the cost of investing in the Investor Class of the Fund with the cost of investing in other mutual funds. The example assumes that you invested $10,000 in the Investor Class of the Fund for the time periods indicated and then redeemed all of your shares at the end of those periods. The example also assumes that your investment had a 5% return each year and that operating expenses (as a percentage of net assets) of the Fund’s Investor Class remained the same. This example reflects contractual fee waivers and reimbursements through January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Wasatch Micro Cap Fund | Investor Class | USD ($)	193	597	1,026	2,222

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). Higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 31% of the average value of its portfolio.

PRINCIPAL STRATEGIES

The Fund invests primarily in growing micro cap companies.
Under normal market conditions, we will invest at least 80% of the Fund’s net assets (plus borrowings for investment purposes) in the equity securities of micro-capitalization companies. The Fund considers a company to be a micro-capitalization company if its market capitalization, at the time of purchase, is less than the larger of $1.5 billion or the market capitalization of the largest company in the Russell Microcap Index as of its most recent reconstitution date. Equity securities include common stock, preferred stock and securities convertible into common stock, warrants and rights, and other securities with equity characteristics (for example, participatory notes or derivatives linked to a basket of underlying equity securities, certain options on common stock, and exchange-traded funds). The Russell Microcap Index reconstitution date is typically each year on or around July 1. As of the 2015 reconstitution date, the market capitalization of the largest company in the Russell Microcap Index was $1.33 billion. The market capitalization of the largest company in the Russell Microcap Index is subject to change at its next reconstitution date.
The Fund may invest up to 30% of its total assets at the time of purchase in securities issued by foreign companies in developed or emerging markets. Securities issued by companies incorporated outside the United States whose securities are principally traded in the United States are not defined as foreign companies and are not subject to this limitation.
We focus on companies that we consider to be high quality, and we use a process of “bottom-up” fundamental analysis to look for companies that we believe have the potential to grow faster than the domestic gross domestic product (GDP) of the United States. Our analysis may include studying a company’s financial statements, building proprietary financial models, visiting company facilities, and meeting with executive management, suppliers and customers.
The Fund seeks to purchase stocks at prices we believe are reasonable relative to our projection of a company’s long term earnings growth rate. The Fund’s secondary objective of income is achieved when fast growing portfolio companies pay dividends, generated by cash flow, typically after achieving growth targets.
The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, financials, health care, industrials and information technology.
The Fund may invest in initial public offerings (IPOs).

PRINCIPAL RISKS

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
The Fund is subject to the following principal investment risks:
Stock Market Risk. The Fund’s investments may decline in value due to movements in the overall stock market.
Stock Selection Risk. The Fund’s investments may decline in value even when the overall stock market is not in a general decline.
Foreign Securities Risk. Foreign securities are generally more volatile and less liquid than U.S. securities. Further, foreign securities may be subject to additional risks not associated with investments in U.S. securities. Differences in the economic and political environment, the amount of available public information, the degree of market regulation, and financial reporting, accounting and auditing standards, and, in the case of foreign currency-denominated securities, fluctuations in currency exchange rates, can have a significant effect on the value of a foreign security.
Emerging Markets Risk. In addition to the risks of investing in foreign securities in general, the risks of investing in the securities of companies domiciled in emerging market countries include increased political or social instability, economies based on only a few industries, unstable currencies, runaway inflation, highly volatile securities markets, unpredictable shifts in policies relating to foreign investments, lack of protection for investors against parties that fail to complete transactions, and the potential for government seizure of assets or nationalization of companies.
Micro Cap Company Stock Risk. Micro cap stocks may be very sensitive to changing economic conditions and market downturns because the issuers often have narrow markets for their products and services, fewer product lines, and more limited managerial and financial resources than larger issuers. The stocks of micro cap companies may therefore be more volatile and the ability to sell these stocks at a desirable time or price may be more limited.
Growth Stock Risk. Growth stock prices may be more sensitive to changes in companies’ current or expected earnings than the prices of other stocks, and growth stock prices may fall or may not appreciate in step with the broader securities markets.
Sector Weightings Risk. To the extent the Fund emphasizes, from time to time, investments in a particular sector, the Fund will be subject to a greater degree to the risks particular to that sector, including the sectors described below. Market conditions, interest rates, and economic, regulatory, or financial developments could significantly affect all the securities in a single sector. If the Fund invests in a few sectors, it may have increased exposure to the price movements of those sectors.
Consumer Discretionary Sector Risk. Industries in the consumer discretionary sector, such as consumer durables, hotels, restaurants, media, retailing, and automobiles, may be significantly impacted by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.
Financials Sector Risk. The financials sector is subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by the availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.
Health Care Sector Risk. Health care companies are strongly affected by worldwide scientific or technological developments. Their products may rapidly become obsolete. Many health care companies are also subject to significant government regulation and may be affected by changes in government policies.
Industrials Sector Risk. Industries in the industrials sector include companies engaged in the production, distribution or service of products or equipment for manufacturing, agriculture, forestry, mining, and construction, and can be significantly affected by general economic trends, including such factors as employment and economic growth, interest rate changes, changes in consumer spending, legislative and government regulation and spending, import controls, commodity prices, and worldwide competition.
Information Technology Sector Risk. Stocks of information technology companies may be volatile because issuers are sensitive to rapid obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions. Information technology stocks, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market.
Initial Public Offerings (IPOs) Risk. IPOs involve a higher degree of risk because companies involved in IPOs generally have limited operating histories and their prospects for future profitability are uncertain. Prices of IPOs may also be unstable due to the absence of a prior public market, the small number of shares available for trading and limited investor information.

HISTORICAL PERFORMANCE

The following tables provide information on how the Investor Class of the Fund has performed over time. The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future. The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The table below is designed to help you evaluate your risk tolerance by showing the best and worst quarterly performance of the Fund’s Investor Class for the years shown in the bar chart. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund. Performance information is updated regularly and is available on the Fund’s website www.WasatchFunds.com.

WASATCH MICRO CAP FUND — INVESTOR CLASS
Year by Year Total Returns

Best and Worst Quarterly Returns

Best — 6/30/2009	27.00%
Worst — 12/31/2008	-31.16%

Average Annual Total Returns — (as of 12/31/15)

Average Annual Total Returns - Wasatch Micro Cap Fund	1 Year	5 Years	10 Years
Investor Class	(1.12%)	8.46%	5.49%
Investor Class | Return After Taxes on Distributions	(4.43%)	7.49%	4.53%
Investor Class | Return After Taxes on Distributions and Sale of Fund Shares	2.15%	6.69%	4.45%
Russell Microcap® Index (reflects no deductions for fees, expenses or taxes)	(5.16%)	9.23%	5.13%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

[1] Wasatch Advisors, Inc. (Advisor), the Fund's investment advisor, has contractually agreed to reimburse the Investor Class shares of the Fund for Total Annual Fund Operating Expenses in excess of 1.95% of average daily net assets until at least January 31, 2017 (excluding interest, dividend expense on short sales/interest expense, taxes, brokerage commissions, other investment related costs, acquired fund fees and expenses, and extraordinary expenses, such as litigation and other expenses not incurred in the ordinary course of business). The Board of Trustees is the only party that can terminate the contractual limitation prior to the contract's expiration. The Advisor can rescind the contractual limitation on expenses at any time after its expiration date.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

WASATCH FUNDS TRUST

Prospectus Date

rr_ProspectusDate

Jan. 31, 2016

Wasatch Micro Cap Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

WASATCH MICRO CAP FUND® — SUMMARY

Objective [Heading]

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The Fund’s primary investment objective is long-term growth of capital.

Objective, Secondary [Text Block]

rr_ObjectiveSecondaryTextBlock

Income is a secondary objective, but only when consistent with long-term growth of capital. Currently, we do not expect the Fund’s investments to generate substantial income.

Expense [Heading]

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The tables below describe the fees and expenses that you may pay if you buy, sell or hold Investor Class shares of the Fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT YOU PAY EACH YEAR AS A PERCENTAGE OF THE VALUE OF YOUR INVESTMENT)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

January 31, 2017

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). Higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 31% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

31.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Investor Class of the Fund with the cost of investing in other mutual funds. The example assumes that you invested $10,000 in the Investor Class of the Fund for the time periods indicated and then redeemed all of your shares at the end of those periods. The example also assumes that your investment had a 5% return each year and that operating expenses (as a percentage of net assets) of the Fund’s Investor Class remained the same. This example reflects contractual fee waivers and reimbursements through January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

PRINCIPAL STRATEGIES

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in growing micro cap companies.
Under normal market conditions, we will invest at least 80% of the Fund’s net assets (plus borrowings for investment purposes) in the equity securities of micro-capitalization companies. The Fund considers a company to be a micro-capitalization company if its market capitalization, at the time of purchase, is less than the larger of $1.5 billion or the market capitalization of the largest company in the Russell Microcap Index as of its most recent reconstitution date. Equity securities include common stock, preferred stock and securities convertible into common stock, warrants and rights, and other securities with equity characteristics (for example, participatory notes or derivatives linked to a basket of underlying equity securities, certain options on common stock, and exchange-traded funds). The Russell Microcap Index reconstitution date is typically each year on or around July 1. As of the 2015 reconstitution date, the market capitalization of the largest company in the Russell Microcap Index was $1.33 billion. The market capitalization of the largest company in the Russell Microcap Index is subject to change at its next reconstitution date.
The Fund may invest up to 30% of its total assets at the time of purchase in securities issued by foreign companies in developed or emerging markets. Securities issued by companies incorporated outside the United States whose securities are principally traded in the United States are not defined as foreign companies and are not subject to this limitation.
We focus on companies that we consider to be high quality, and we use a process of “bottom-up” fundamental analysis to look for companies that we believe have the potential to grow faster than the domestic gross domestic product (GDP) of the United States. Our analysis may include studying a company’s financial statements, building proprietary financial models, visiting company facilities, and meeting with executive management, suppliers and customers.
The Fund seeks to purchase stocks at prices we believe are reasonable relative to our projection of a company’s long term earnings growth rate. The Fund’s secondary objective of income is achieved when fast growing portfolio companies pay dividends, generated by cash flow, typically after achieving growth targets.
The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, financials, health care, industrials and information technology.
The Fund may invest in initial public offerings (IPOs).

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, financials, health care, industrials and information technology.

Risk [Heading]

rr_RiskHeading

PRINCIPAL RISKS

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
The Fund is subject to the following principal investment risks:
Stock Market Risk. The Fund’s investments may decline in value due to movements in the overall stock market.
Stock Selection Risk. The Fund’s investments may decline in value even when the overall stock market is not in a general decline.
Foreign Securities Risk. Foreign securities are generally more volatile and less liquid than U.S. securities. Further, foreign securities may be subject to additional risks not associated with investments in U.S. securities. Differences in the economic and political environment, the amount of available public information, the degree of market regulation, and financial reporting, accounting and auditing standards, and, in the case of foreign currency-denominated securities, fluctuations in currency exchange rates, can have a significant effect on the value of a foreign security.
Emerging Markets Risk. In addition to the risks of investing in foreign securities in general, the risks of investing in the securities of companies domiciled in emerging market countries include increased political or social instability, economies based on only a few industries, unstable currencies, runaway inflation, highly volatile securities markets, unpredictable shifts in policies relating to foreign investments, lack of protection for investors against parties that fail to complete transactions, and the potential for government seizure of assets or nationalization of companies.
Micro Cap Company Stock Risk. Micro cap stocks may be very sensitive to changing economic conditions and market downturns because the issuers often have narrow markets for their products and services, fewer product lines, and more limited managerial and financial resources than larger issuers. The stocks of micro cap companies may therefore be more volatile and the ability to sell these stocks at a desirable time or price may be more limited.
Growth Stock Risk. Growth stock prices may be more sensitive to changes in companies’ current or expected earnings than the prices of other stocks, and growth stock prices may fall or may not appreciate in step with the broader securities markets.
Sector Weightings Risk. To the extent the Fund emphasizes, from time to time, investments in a particular sector, the Fund will be subject to a greater degree to the risks particular to that sector, including the sectors described below. Market conditions, interest rates, and economic, regulatory, or financial developments could significantly affect all the securities in a single sector. If the Fund invests in a few sectors, it may have increased exposure to the price movements of those sectors.
Consumer Discretionary Sector Risk. Industries in the consumer discretionary sector, such as consumer durables, hotels, restaurants, media, retailing, and automobiles, may be significantly impacted by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.
Financials Sector Risk. The financials sector is subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by the availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.
Health Care Sector Risk. Health care companies are strongly affected by worldwide scientific or technological developments. Their products may rapidly become obsolete. Many health care companies are also subject to significant government regulation and may be affected by changes in government policies.
Industrials Sector Risk. Industries in the industrials sector include companies engaged in the production, distribution or service of products or equipment for manufacturing, agriculture, forestry, mining, and construction, and can be significantly affected by general economic trends, including such factors as employment and economic growth, interest rate changes, changes in consumer spending, legislative and government regulation and spending, import controls, commodity prices, and worldwide competition.
Information Technology Sector Risk. Stocks of information technology companies may be volatile because issuers are sensitive to rapid obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions. Information technology stocks, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market.
Initial Public Offerings (IPOs) Risk. IPOs involve a higher degree of risk because companies involved in IPOs generally have limited operating histories and their prospects for future profitability are uncertain. Prices of IPOs may also be unstable due to the absence of a prior public market, the small number of shares available for trading and limited investor information.

Risk Lose Money [Text]

rr_RiskLoseMoney

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

HISTORICAL PERFORMANCE

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following tables provide information on how the Investor Class of the Fund has performed over time. The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future. The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The table below is designed to help you evaluate your risk tolerance by showing the best and worst quarterly performance of the Fund’s Investor Class for the years shown in the bar chart. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund. Performance information is updated regularly and is available on the Fund’s website www.WasatchFunds.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.WasatchFunds.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

WASATCH MICRO CAP FUND — INVESTOR CLASS
Year by Year Total Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best and Worst Quarterly Returns

Best — 6/30/2009	27.00%
Worst — 12/31/2008	-31.16%

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns — (as of 12/31/15)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

Wasatch Micro Cap Fund | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Redemption Fee (as a % of amount redeemed on shares held 60 days or less)

rr_RedemptionFeeOverRedemption

2.00%

Exchange Fee

rr_ExchangeFeeOverRedemption

none

Maximum Account Fee

rr_MaximumAccountFeeOverAssets

none

Management Fee

rr_ManagementFeesOverAssets

1.75%

Distribution/Service (12b-1) Fee

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.15%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.90%

^[1]

1 Year

rr_ExpenseExampleYear01

$ 193

3 Years

rr_ExpenseExampleYear03

597

5 Years

rr_ExpenseExampleYear05

1,026

10 Years

rr_ExpenseExampleYear10

$ 2,222

2006

rr_AnnualReturn2006

17.05%

2007

rr_AnnualReturn2007

2.23%

2008

rr_AnnualReturn2008

(49.29%)

2009

rr_AnnualReturn2009

44.37%

2010

rr_AnnualReturn2010

29.76%

2011

rr_AnnualReturn2011

(6.39%)

2012

rr_AnnualReturn2012

11.85%

2013

rr_AnnualReturn2013

44.70%

2014

rr_AnnualReturn2014

0.17%

2015

rr_AnnualReturn2015

(1.12%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

27.00%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(31.16%)

1 Year

rr_AverageAnnualReturnYear01

(1.12%)

5 Years

rr_AverageAnnualReturnYear05

8.46%

10 Years

rr_AverageAnnualReturnYear10

5.49%

Wasatch Micro Cap Fund | Return After Taxes on Distributions | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(4.43%)

5 Years

rr_AverageAnnualReturnYear05

7.49%

10 Years

rr_AverageAnnualReturnYear10

4.53%

Wasatch Micro Cap Fund | Return After Taxes on Distributions and Sale of Fund Shares | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

2.15%

5 Years

rr_AverageAnnualReturnYear05

6.69%

10 Years

rr_AverageAnnualReturnYear10

4.45%

Wasatch Micro Cap Fund | Russell Microcap® Index (reflects no deductions for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(5.16%)

5 Years

rr_AverageAnnualReturnYear05

9.23%

10 Years

rr_AverageAnnualReturnYear10

5.13%

[1] Wasatch Advisors, Inc. (Advisor), the Fund's investment advisor, has contractually agreed to reimburse the Investor Class shares of the Fund for Total Annual Fund Operating Expenses in excess of 1.95% of average daily net assets until at least January 31, 2017 (excluding interest, dividend expense on short sales/interest expense, taxes, brokerage commissions, other investment related costs, acquired fund fees and expenses, and extraordinary expenses, such as litigation and other expenses not incurred in the ordinary course of business). The Board of Trustees is the only party that can terminate the contractual limitation prior to the contract's expiration. The Advisor can rescind the contractual limitation on expenses at any time after its expiration date.

XML

Wasatch Micro Cap Value Fund

WASATCH MICRO CAP VALUE FUND® — SUMMARY

INVESTMENT OBJECTIVE

The Fund’s investment objective is long-term growth of capital.

FEES AND EXPENSES OF THE FUND

The tables below describe the fees and expenses that you may pay if you buy, sell or hold Investor Class shares of the Fund.

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)

Shareholder Fees	Wasatch Micro Cap Value Fund Investor Class Shares
Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)	none
Redemption Fee (as a % of amount redeemed on shares held 60 days or less)	2.00%
Exchange Fee	none
Maximum Account Fee	none

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT YOU PAY EACH YEAR AS A PERCENTAGE OF THE VALUE OF YOUR INVESTMENT)

Annual Fund Operating Expenses	Wasatch Micro Cap Value Fund Investor Class Shares
Management Fee	1.75%
Distribution/Service (12b-1) Fee	none
Other Expenses	0.26%
Interest Expense	0.01%
Acquired Fund Fees and Expenses	0.07%
Total Annual Fund Operating Expenses	2.09%	[1]
Expense Reimbursement	(0.06%)	[2]
Total Annual Fund Operating Expenses After Expense Reimbursement	2.03%

EXAMPLE

This example is intended to help you compare the cost of investing in the Investor Class of the Fund with the cost of investing in other mutual funds. The example assumes that you invested $10,000 in the Investor Class of the Fund for the time periods indicated and then redeemed all of your shares at the end of those periods. The example also assumes that your investment had a 5% return each year and that operating expenses (as a percentage of net assets) of the Fund’s Investor Class remained the same. This example reflects contractual fee waivers and reimbursements through January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
Wasatch Micro Cap Value Fund | Investor Class | USD ($)	206	649	1,118	2,416

PORTFOLIO TURNOVER

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). Higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 53% of the average value of its portfolio.

PRINCIPAL STRATEGIES

The Fund invests primarily in micro cap companies.
Under normal market conditions, we will invest at least 80% of the Fund’s net assets (plus borrowings for investment purposes) in the equity securities of micro-capitalization companies. The Fund considers a company to be a micro-capitalization company if its market capitalization, at the time of purchase, is less than the larger of $1.5 billion or the market capitalization of the largest company in the Russell Microcap Index as of its most recent reconstitution date. Equity securities include common stock, preferred stock and securities convertible into common stock, warrants and rights, and other securities with equity characteristics (for example, participatory notes or derivatives linked to a basket of underlying equity securities, certain options on common stock, and exchange-traded funds). The Russell Microcap Index reconstitution date is typically each year on or around July 1. As of the 2015 reconstitution date, the market capitalization of the largest company in the Russell Microcap Index was $1.33 billion. The market capitalization of the largest company in the Russell Microcap Index is subject to change at its next reconstitution date.
The Fund may invest up to 30% of its total assets at the time of purchase in securities issued by foreign companies in developed or emerging markets. Securities issued by companies incorporated outside the United States whose securities are principally traded in the United States are not defined as foreign companies and are not subject to this limitation.
The Fund may invest in initial public offerings (IPOs).
While the Fund primarily invests in value companies, it may also invest in growth companies if the Advisor believes that a company’s current valuation is at a sufficient discount to its projected long term earnings growth rate.
We use a “bottom-up” process of fundamental analysis to look for individual companies that we believe are temporarily undervalued but have significant potential for stock price appreciation. Our analysis may include studying a company’s financial statements, visiting company facilities, and meeting with executive management, suppliers and customers.
We typically look for companies that we believe fall into one of these three categories at the time of purchase:

• Undiscovered Gems — Companies with good growth potential which have yet to be broadly discovered by Wall Street analysts, thus leaving them attractively undervalued relative to their expected growth.
• Fallen Angels — High quality growth companies that have experienced a temporary setback and therefore have appealing valuations relative to their long term growth potential.
• Value Momentum — Valuation that is inexpensive relative to history, but catalyst for future growth has been identified.

The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, consumer staples, financials, health care, industrials and information technology.

PRINCIPAL RISKS

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
The Fund is subject to the following principal investment risks:
Stock Market Risk. The Fund’s investments may decline in value due to movements in the overall stock market.
Stock Selection Risk. The Fund’s investments may decline in value even when the overall stock market is not in a general decline.
Foreign Securities Risk. Foreign securities are generally more volatile and less liquid than U.S. securities. Further, foreign securities may be subject to additional risks not associated with investments in U.S. securities. Differences in the economic and political environment, the amount of available public information, the degree of market regulation, and financial reporting, accounting and auditing standards, and, in the case of foreign currency-denominated securities, fluctuations in currency exchange rates, can have a significant effect on the value of a foreign security.
Emerging Markets Risk. In addition to the risks of investing in foreign securities in general, the risks of investing in the securities of companies domiciled in emerging market countries include increased political or social instability, economies based on only a few industries, unstable currencies, runaway inflation, highly volatile securities markets, unpredictable shifts in policies relating to foreign investments, lack of protection for investors against parties that fail to complete transactions, and the potential for government seizure of assets or nationalization of companies.
Micro Cap Company Stock Risk. Micro cap stocks may be very sensitive to changing economic conditions and market downturns because the issuers often have narrow markets for their products and services, fewer product lines, and more limited managerial and financial resources than larger issuers. The stocks of micro cap companies may therefore be more volatile and the ability to sell these stocks at a desirable time or price may be more limited.
Value Investing Risk. A value investing strategy attempts to identify strong companies with stocks selling at a discount from their perceived true worth. It is subject to the risk that the stocks’ intrinsic values may never be fully recognized or realized by the market, their prices may go down, or that stocks judged to be undervalued may actually be appropriately priced.
Initial Public Offerings (IPOs) Risk. IPOs involve a higher degree of risk because companies involved in IPOs generally have limited operating histories and their prospects for future profitability are uncertain. Prices of IPOs may also be unstable due to the absence of a prior public market, the small number of shares available for trading and limited investor information.
Sector Weightings Risk. To the extent the Fund emphasizes, from time to time, investments in a particular sector, the Fund will be subject to a greater degree to the risks particular to that sector, including the sectors described below. Market conditions, interest rates, and economic, regulatory, or financial developments could significantly affect all the securities in a single sector. If the Fund invests in a few sectors, it may have increased exposure to the price movements of those sectors.
Consumer Discretionary Sector Risk. Industries in the consumer discretionary sector, such as consumer durables, hotels, restaurants, media, retailing, and automobiles, may be significantly impacted by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.
Consumer Staples Sector Risk. The consumer staples sector may be affected by marketing campaigns, changes in consumer demands, government regulations and changes in commodity prices.
Financials Sector Risk. The financials sector is subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by the availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.
Health Care Sector Risk. Health care companies are strongly affected by worldwide scientific or technological developments. Their products may rapidly become obsolete. Many health care companies are also subject to significant government regulation and may be affected by changes in government policies.
Industrials Sector Risk. Industries in the industrials sector include companies engaged in the production, distribution or service of products or equipment for manufacturing, agriculture, forestry, mining, and construction, and can be significantly affected by general economic trends, including such factors as employment and economic growth, interest rate changes, changes in consumer spending, legislative and government regulation and spending, import controls, commodity prices, and worldwide competition.
Information Technology Sector Risk. Stocks of information technology companies may be volatile because issuers are sensitive to rapid obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions. Information technology stocks, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market.
Growth Stock Risk. Growth stock prices may be more sensitive to changes in companies’ current or expected earnings than the prices of other stocks, and growth stock prices may fall or may not appreciate in step with the broader securities markets.

HISTORICAL PERFORMANCE

The following tables provide information on how the Investor Class of the Fund has performed over time. The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future. The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The table below is designed to help you evaluate your risk tolerance by showing the best and worst quarterly performance of the Fund’s Investor Class for the years shown in the bar chart. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund. Performance information is updated regularly and is available on the Fund’s website www.WasatchFunds.com.

WASATCH MICRO CAP VALUE FUND — INVESTOR CLASS
Year by Year Total Returns

Best and Worst Quarterly Returns

Best — 6/30/2009	40.00%
Worst — 12/31/2008	-26.67%

Average Annual Total Returns — (as of 12/31/15)

Average Annual Total Returns - Wasatch Micro Cap Value Fund	1 Year	5 Years	10 Years
Investor Class	7.19%	10.76%	9.52%
Investor Class | Return After Taxes on Distributions	4.28%	8.26%	7.56%
Investor Class | Return After Taxes on Distributions and Sale of Fund Shares	6.18%	8.45%	7.57%
Russell Microcap® Index (reflects no deductions for fees, expenses or taxes)	(5.16%)	9.23%	5.13%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

[1] The Total Annual Fund Operating Expenses may not equal the expense ratio stated in the Fund's most recent Annual Report and Financial Highlights, which reflects the operating expenses of the Fund and does not include Acquired Fund Fees and Expenses.

[2] Wasatch Advisors, Inc. (Advisor), the Fund's investment advisor, has contractually agreed to reimburse the Investor Class shares of the Fund for Total Annual Fund Operating Expenses in excess of 1.95% of average daily net assets until at least January 31, 2017 (excluding interest, dividend expense on short sales/interest expense, taxes, brokerage commissions, other investment related costs, acquired fund fees and expenses, and extraordinary expenses, such as litigation and other expenses not incurred in the ordinary course of business). The Board of Trustees is the only party that can terminate the contractual limitation prior to the contract's expiration. The Advisor can rescind the contractual limitation on expenses at any time after its expiration date.

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Registrant Name

dei_EntityRegistrantName

WASATCH FUNDS TRUST

Prospectus Date

rr_ProspectusDate

Jan. 31, 2016

Wasatch Micro Cap Value Fund

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

rr_RiskReturnHeading

WASATCH MICRO CAP VALUE FUND® — SUMMARY

Objective [Heading]

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The Fund’s investment objective is long-term growth of capital.

Expense [Heading]

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The tables below describe the fees and expenses that you may pay if you buy, sell or hold Investor Class shares of the Fund.

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT YOU PAY EACH YEAR AS A PERCENTAGE OF THE VALUE OF YOUR INVESTMENT)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

January 31, 2017

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). Higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 53% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

53.00%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

rr_ExpensesNotCorrelatedToRatioDueToAcquiredFundFees

The Total Annual Fund Operating Expenses may not equal the expense ratio stated in the Fund’s most recent Annual Report and Financial Highlights, which reflects the operating expenses of the Fund and does not include Acquired Fund Fees and Expenses.

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Investor Class of the Fund with the cost of investing in other mutual funds. The example assumes that you invested $10,000 in the Investor Class of the Fund for the time periods indicated and then redeemed all of your shares at the end of those periods. The example also assumes that your investment had a 5% return each year and that operating expenses (as a percentage of net assets) of the Fund’s Investor Class remained the same. This example reflects contractual fee waivers and reimbursements through January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

PRINCIPAL STRATEGIES

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in micro cap companies.
Under normal market conditions, we will invest at least 80% of the Fund’s net assets (plus borrowings for investment purposes) in the equity securities of micro-capitalization companies. The Fund considers a company to be a micro-capitalization company if its market capitalization, at the time of purchase, is less than the larger of $1.5 billion or the market capitalization of the largest company in the Russell Microcap Index as of its most recent reconstitution date. Equity securities include common stock, preferred stock and securities convertible into common stock, warrants and rights, and other securities with equity characteristics (for example, participatory notes or derivatives linked to a basket of underlying equity securities, certain options on common stock, and exchange-traded funds). The Russell Microcap Index reconstitution date is typically each year on or around July 1. As of the 2015 reconstitution date, the market capitalization of the largest company in the Russell Microcap Index was $1.33 billion. The market capitalization of the largest company in the Russell Microcap Index is subject to change at its next reconstitution date.
The Fund may invest up to 30% of its total assets at the time of purchase in securities issued by foreign companies in developed or emerging markets. Securities issued by companies incorporated outside the United States whose securities are principally traded in the United States are not defined as foreign companies and are not subject to this limitation.
The Fund may invest in initial public offerings (IPOs).
While the Fund primarily invests in value companies, it may also invest in growth companies if the Advisor believes that a company’s current valuation is at a sufficient discount to its projected long term earnings growth rate.
We use a “bottom-up” process of fundamental analysis to look for individual companies that we believe are temporarily undervalued but have significant potential for stock price appreciation. Our analysis may include studying a company’s financial statements, visiting company facilities, and meeting with executive management, suppliers and customers.
We typically look for companies that we believe fall into one of these three categories at the time of purchase:

• Undiscovered Gems — Companies with good growth potential which have yet to be broadly discovered by Wall Street analysts, thus leaving them attractively undervalued relative to their expected growth.
• Fallen Angels — High quality growth companies that have experienced a temporary setback and therefore have appealing valuations relative to their long term growth potential.
• Value Momentum — Valuation that is inexpensive relative to history, but catalyst for future growth has been identified.

The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, consumer staples, financials, health care, industrials and information technology.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

The Fund may invest a large percentage of its assets in a few sectors, including consumer discretionary, consumer staples, financials, health care, industrials and information technology.

Risk [Heading]

rr_RiskHeading

PRINCIPAL RISKS

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund. An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.
The Fund is subject to the following principal investment risks:
Stock Market Risk. The Fund’s investments may decline in value due to movements in the overall stock market.
Stock Selection Risk. The Fund’s investments may decline in value even when the overall stock market is not in a general decline.
Foreign Securities Risk. Foreign securities are generally more volatile and less liquid than U.S. securities. Further, foreign securities may be subject to additional risks not associated with investments in U.S. securities. Differences in the economic and political environment, the amount of available public information, the degree of market regulation, and financial reporting, accounting and auditing standards, and, in the case of foreign currency-denominated securities, fluctuations in currency exchange rates, can have a significant effect on the value of a foreign security.
Emerging Markets Risk. In addition to the risks of investing in foreign securities in general, the risks of investing in the securities of companies domiciled in emerging market countries include increased political or social instability, economies based on only a few industries, unstable currencies, runaway inflation, highly volatile securities markets, unpredictable shifts in policies relating to foreign investments, lack of protection for investors against parties that fail to complete transactions, and the potential for government seizure of assets or nationalization of companies.
Micro Cap Company Stock Risk. Micro cap stocks may be very sensitive to changing economic conditions and market downturns because the issuers often have narrow markets for their products and services, fewer product lines, and more limited managerial and financial resources than larger issuers. The stocks of micro cap companies may therefore be more volatile and the ability to sell these stocks at a desirable time or price may be more limited.
Value Investing Risk. A value investing strategy attempts to identify strong companies with stocks selling at a discount from their perceived true worth. It is subject to the risk that the stocks’ intrinsic values may never be fully recognized or realized by the market, their prices may go down, or that stocks judged to be undervalued may actually be appropriately priced.
Initial Public Offerings (IPOs) Risk. IPOs involve a higher degree of risk because companies involved in IPOs generally have limited operating histories and their prospects for future profitability are uncertain. Prices of IPOs may also be unstable due to the absence of a prior public market, the small number of shares available for trading and limited investor information.
Sector Weightings Risk. To the extent the Fund emphasizes, from time to time, investments in a particular sector, the Fund will be subject to a greater degree to the risks particular to that sector, including the sectors described below. Market conditions, interest rates, and economic, regulatory, or financial developments could significantly affect all the securities in a single sector. If the Fund invests in a few sectors, it may have increased exposure to the price movements of those sectors.
Consumer Discretionary Sector Risk. Industries in the consumer discretionary sector, such as consumer durables, hotels, restaurants, media, retailing, and automobiles, may be significantly impacted by the performance of the overall economy, interest rates, competition, consumer confidence and spending, and changes in demographics and consumer tastes.
Consumer Staples Sector Risk. The consumer staples sector may be affected by marketing campaigns, changes in consumer demands, government regulations and changes in commodity prices.
Financials Sector Risk. The financials sector is subject to extensive government regulation, can be subject to relatively rapid change due to increasingly blurred distinctions between service segments, and can be significantly affected by the availability and cost of capital funds, changes in interest rates, the rate of corporate and consumer debt defaults, and price competition.
Health Care Sector Risk. Health care companies are strongly affected by worldwide scientific or technological developments. Their products may rapidly become obsolete. Many health care companies are also subject to significant government regulation and may be affected by changes in government policies.
Industrials Sector Risk. Industries in the industrials sector include companies engaged in the production, distribution or service of products or equipment for manufacturing, agriculture, forestry, mining, and construction, and can be significantly affected by general economic trends, including such factors as employment and economic growth, interest rate changes, changes in consumer spending, legislative and government regulation and spending, import controls, commodity prices, and worldwide competition.
Information Technology Sector Risk. Stocks of information technology companies may be volatile because issuers are sensitive to rapid obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions. Information technology stocks, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market.
Growth Stock Risk. Growth stock prices may be more sensitive to changes in companies’ current or expected earnings than the prices of other stocks, and growth stock prices may fall or may not appreciate in step with the broader securities markets.

Risk Lose Money [Text]

rr_RiskLoseMoney

All investments carry some degree of risk that will affect the value of the Fund, its investment performance and the price of its shares. As a result, you may lose money if you invest in the Fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

HISTORICAL PERFORMANCE

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following tables provide information on how the Investor Class of the Fund has performed over time. The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future. The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The table below is designed to help you evaluate your risk tolerance by showing the best and worst quarterly performance of the Fund’s Investor Class for the years shown in the bar chart. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund. Performance information is updated regularly and is available on the Fund’s website www.WasatchFunds.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart below is intended to provide you with an indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year, as represented by the Investor Class of the Fund. The average annual total return table below allows you to compare the Fund’s performance over the time periods indicated to that of a broad-based market index composed of securities similar to those held by the Fund.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

www.WasatchFunds.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The past performance, before and after taxes, of the Fund’s Investor Class is not necessarily an indication of how these shares will perform in the future.

Bar Chart [Heading]

rr_BarChartHeading

WASATCH MICRO CAP VALUE FUND — INVESTOR CLASS
Year by Year Total Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best and Worst Quarterly Returns

Best — 6/30/2009	40.00%
Worst — 12/31/2008	-26.67%

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns — (as of 12/31/15)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

Performance Table Explanation after Tax Higher

rr_PerformanceTableExplanationAfterTaxHigher

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. The after-tax returns are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

The Fund’s returns after taxes on distributions and sale of Fund shares may be higher than returns before taxes and after taxes on distributions because they include the effect of a tax benefit an investor may receive from the capital losses that would have been incurred.

Wasatch Micro Cap Value Fund | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) Imposed on Purchases (as a % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Redemption Fee (as a % of amount redeemed on shares held 60 days or less)

rr_RedemptionFeeOverRedemption

2.00%

Exchange Fee

rr_ExchangeFeeOverRedemption

none

Maximum Account Fee

rr_MaximumAccountFeeOverAssets

none

Management Fee

rr_ManagementFeesOverAssets

1.75%

Distribution/Service (12b-1) Fee

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.26%

Interest Expense

rr_Component1OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.07%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.09%

^[1]

Expense Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.06%)

^[2]

Total Annual Fund Operating Expenses After Expense Reimbursement

rr_NetExpensesOverAssets

2.03%

1 Year

rr_ExpenseExampleYear01

$ 206

3 Years

rr_ExpenseExampleYear03

649

5 Years

rr_ExpenseExampleYear05

1,118

10 Years

rr_ExpenseExampleYear10

$ 2,416

2006

rr_AnnualReturn2006

28.83%

2007

rr_AnnualReturn2007

7.02%

2008

rr_AnnualReturn2008

(47.20%)

2009

rr_AnnualReturn2009

70.40%

2010

rr_AnnualReturn2010

20.09%

2011

rr_AnnualReturn2011

(10.41%)

2012

rr_AnnualReturn2012

22.10%

2013

rr_AnnualReturn2013

43.23%

2014

rr_AnnualReturn2014

(0.75%)

2015

rr_AnnualReturn2015

7.19%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

40.00%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.67%)

1 Year

rr_AverageAnnualReturnYear01

7.19%

5 Years

rr_AverageAnnualReturnYear05

10.76%

10 Years

rr_AverageAnnualReturnYear10

9.52%

Wasatch Micro Cap Value Fund | Return After Taxes on Distributions | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

4.28%

5 Years

rr_AverageAnnualReturnYear05

8.26%

10 Years

rr_AverageAnnualReturnYear10

7.56%

Wasatch Micro Cap Value Fund | Return After Taxes on Distributions and Sale of Fund Shares | Investor Class Shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

6.18%

5 Years

rr_AverageAnnualReturnYear05

8.45%

10 Years

rr_AverageAnnualReturnYear10

7.57%

Wasatch Micro Cap Value Fund | Russell Microcap® Index (reflects no deductions for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(5.16%)

5 Years

rr_AverageAnnualReturnYear05

9.23%

10 Years

rr_AverageAnnualReturnYear10

5.13%

[1] The Total Annual Fund Operating Expenses may not equal the expense ratio stated in the Fund's most recent Annual Report and Financial Highlights, which reflects the operating expenses of the Fund and does not include Acquired Fund Fees and Expenses.

[2] Wasatch Advisors, Inc. (Advisor), the Fund's investment advisor, has contractually agreed to reimburse the Investor Class shares of the Fund for Total Annual Fund Operating Expenses in excess of 1.95% of average daily net assets until at least January 31, 2017 (excluding interest, dividend expense on short sales/interest expense, taxes, brokerage commissions, other investment related costs, acquired fund fees and expenses, and extraordinary expenses, such as litigation and other expenses not incurred in the ordinary course of business). The Board of Trustees is the only party that can terminate the contractual limitation prior to the contract's expiration. The Advisor can rescind the contractual limitation on expenses at any time after its expiration date.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	WASATCH FUNDS TRUST
Prospectus Date	rr_ProspectusDate	Jan. 31, 2016
Document Creation Date	dei_DocumentCreationDate	Feb. 01, 2016