Income Taxes	3 Months Ended
Mar. 31, 2019
Income Taxes.
Income Taxes	NOTE 8. Income Taxes The IRS has completed its field examination of the Company’s U.S. federal income tax returns for the years 2005 to 2014, and 2016, but the years have not closed as the Company is in the process of resolving open issues. The Company remains under examination by the IRS for its U.S. federal income tax returns for the years 2015, 2017 and 2018. In addition to the U.S. federal examination, there is also audit activity in several U.S. state and foreign jurisdictions. As of March 31, 2019, no taxing authority proposed significant adjustments to the Company’s tax positions for which the Company is not adequately reserved. It is reasonably possible that the amount of unrecognized tax benefits could significantly change within the next 12 months. The Company has ongoing federal, state and international income tax audits in various jurisdictions and evaluates uncertain tax positions that may be challenged by local tax authorities and not fully sustained. These uncertain tax positions are reviewed on an ongoing basis and adjusted in light of facts and circumstances including progression of tax audits, developments in case law and closing of statutes of limitation. At this time, the Company is not able to estimate the range by which these potential events could impact 3M’s unrecognized tax benefits in the next 12 months. The total amounts of unrecognized tax benefits that, if recognized, would affect the effective tax rate as of March 31, 2019 and December 31, 2018 are $679 million and $655 million, respectively. The Company recognizes interest and penalties accrued related to unrecognized tax benefits in tax expense. The Company recognized in the consolidated statement of income on a gross basis approximately $6 million and $9 million of expense for the three months ended March 31, 2019 and March 31, 2018, respectively. At March 31, 2019 and December 31, 2018, accrued interest and penalties in the consolidated balance sheet on a gross basis were $75 million and $69 million, respectively. Included in these interest and penalty amounts are interest and penalties related to tax positions for which the ultimate deductibility is highly certain but for which there is uncertainty about the timing of such deductibility. The provision for income taxes is determined using the asset and liability approach. Under this approach, a valuation allowance is recorded to reduce its deferred tax assets when uncertainty regarding their realizability exists. As of March 31, 2019 and December 31, 2018, the Company had valuation allowances of $84 million and $67 million on its deferred tax assets, respectively. The effective tax rate for the first quarter of 2019 was 17.9 percent, compared to 37.2 percent in the first quarter of 2018, a decrease of 19.3 percentage points. Primary factors that decreased the Company’s effective tax rate included significant events such as measurement period adjustments related to TCJA and significant litigation-related charges, in addition to increased benefit from research and development credits. These decreases were partially offset by the composition of geographic mix of income before taxes and the effects of the international tax provisions from U.S. tax reform, which increased the Company’s effective tax rate. The TCJA was enacted in December 2017. Among other things, the TCJA reduced the U.S. federal corporate tax rate from 35 percent to 21 percent beginning in 2018, required companies to pay a one-time transition tax on previously unremitted earnings of non-U.S. subsidiaries that were previously tax deferred and created new taxes on certain foreign sourced earnings. The SEC staff issued Staff Accounting Bulletin 118, which provided a measurement period of up to one year from the TCJA’s enactment date for companies to complete their accounting under ASC 740. During the first quarter of 2018, 3M recognized a measurement period adjustment resulting in an additional tax expense of $217 million to its provisional accounting. Refer to Note 10 in 3M’s 2018 Annual Report on Form 10-K for more information on the impact of TCJA. The Company adopted ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, as described in Note 1, on January 1, 2019. The purpose of this ASU was to allow a reclassification to retained earnings of one-time income tax effects stranded in accumulated other comprehensive income (AOCI) arising from the change in the U.S. federal corporate tax rate as a result of TCJA. The effect of this adoption resulted in a reclassification between retained earnings and AOCI, which increased retained earnings by approximately $0.9 billion, with an offsetting increase to accumulated other comprehensive loss for the same amount.

NOTE 8. Income Taxes

The IRS has completed its field examination of the Company’s U.S. federal income tax returns for the years 2005 to 2014, and 2016, but the years have not closed as the Company is in the process of resolving open issues. The Company remains under examination by the IRS for its U.S. federal income tax returns for the years 2015, 2017 and 2018. In addition to the U.S. federal examination, there is also audit activity in several U.S. state and foreign jurisdictions. As of March 31, 2019, no taxing authority proposed significant adjustments to the Company’s tax positions for which the Company is not adequately reserved.

It is reasonably possible that the amount of unrecognized tax benefits could significantly change within the next 12 months. The Company has ongoing federal, state and international income tax audits in various jurisdictions and evaluates uncertain tax positions that may be challenged by local tax authorities and not fully sustained. These uncertain tax positions are reviewed on an ongoing basis and adjusted in light of facts and circumstances including progression of tax audits, developments in case law and closing of statutes of limitation. At this time, the Company is not able to estimate the range by which these potential events could impact 3M’s unrecognized tax benefits in the next 12 months. The total amounts of unrecognized tax benefits that, if recognized, would affect the effective tax rate as of March 31, 2019 and December 31, 2018 are $679 million and $655 million, respectively.

The Company recognizes interest and penalties accrued related to unrecognized tax benefits in tax expense. The Company recognized in the consolidated statement of income on a gross basis approximately $6 million and $9 million of expense for the three months ended March 31, 2019 and March 31, 2018, respectively. At March 31, 2019 and December 31, 2018, accrued interest and penalties in the consolidated balance sheet on a gross basis were $75 million and $69 million, respectively. Included in these interest and penalty amounts are interest and penalties related to tax positions for which the ultimate deductibility is highly certain but for which there is uncertainty about the timing of such deductibility.

The provision for income taxes is determined using the asset and liability approach. Under this approach, a valuation allowance is recorded to reduce its deferred tax assets when uncertainty regarding their realizability exists. As of March 31, 2019 and December 31, 2018, the Company had valuation allowances of $84 million and $67 million on its deferred tax assets, respectively.

The effective tax rate for the first quarter of 2019 was 17.9 percent, compared to 37.2 percent in the first quarter of 2018, a decrease of 19.3 percentage points. Primary factors that decreased the Company’s effective tax rate included significant events such as measurement period adjustments related to TCJA and significant litigation-related charges, in addition to increased benefit from research and development credits. These decreases were partially offset by the composition of geographic mix of income before taxes and the effects of the international tax provisions from U.S. tax reform, which increased the Company’s effective tax rate.

The TCJA was enacted in December 2017. Among other things, the TCJA reduced the U.S. federal corporate tax rate from 35 percent to 21 percent beginning in 2018, required companies to pay a one-time transition tax on previously unremitted earnings of non-U.S. subsidiaries that were previously tax deferred and created new taxes on certain foreign sourced earnings. The SEC staff issued Staff Accounting Bulletin 118, which provided a measurement period of up to one year from the TCJA’s enactment date for companies to complete their accounting under ASC 740. During the first quarter of 2018, 3M recognized a measurement period adjustment resulting in an additional tax expense of $217 million to its provisional accounting. Refer to Note 10 in 3M’s 2018 Annual Report on Form 10-K for more information on the impact of TCJA.

The Company adopted ASU No. 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, as described in Note 1, on January 1, 2019. The purpose of this ASU was to allow a reclassification to retained earnings of one-time income tax effects stranded in accumulated other comprehensive income (AOCI) arising from the change in the U.S. federal corporate tax rate as a result of TCJA. The effect of this adoption resulted in a reclassification between retained earnings and AOCI, which increased retained earnings by approximately $0.9 billion, with an offsetting increase to accumulated other comprehensive loss for the same amount.