In general. Title 26 U.S.C. 7503 provides that when the last day prescribed under provisions of 26 U.S.C. enforced and administered by the Bureau, for the performance of any act falls on a Saturday, Sunday, or legal holiday, such act shall be considered performed timely if performed on the next succeeding day which is not a Saturday, Sunday, or legal holiday. For this purpose, any authorized extension of time shall be included in the determining of the last day for performance of any act. Title 26 U.S.C. 7503 is not applicable to the filing of returns and payment of tax under 26 U.S.C. subtitle E. Title 26 U.S.C. 7503 is applicable only in case an act is required under authority of any provisions of 26 U.S.C. enforced and administered by the Bureau to be performed on or before a prescribed date or within a prescribed period. Title 26 U.S.C. 7503 applies to acts to be performed by the taxpayer (such as the filing of a claim for credit or refund of tax) and acts to be performed by the appropriate TTB officer, (such as, the giving of any notice with respect to, or making any demand for the payment of, any tax; the assessment or collection of any tax). For rules concerning the payment of any tax or the filing of any return required under the authority of 26 U.S.C. 4181 and 4182 relating to firearms and ammunition or subtitle E relating to alcohol, tobacco products, and cigarette papers and tubes, see 26 U.S.C. 5061, 5703, and 6302 and the regulations covering the specific commodity.

Legal holidays. (1) For the purpose of 26 U.S.C. 7503, the term “legal holiday” includes the legal holidays in the District of Columbia. Such legal holidays found in 5 U.S.C. 6103(a), as enacted and made effective by the Act of November 2, 1983 (97 Stat. 917), are:

January 1, New Year's Day,

Third Monday in January, Birthday of Martin Luther King, Jr.,

January 20, when such day is Inauguration Day,

Third Monday in February, Washington's Birthday,

Last Monday in May, Memorial Day,

July 4, Independence Day,

First Monday in September, Labor Day,

Second Monday in October, Columbus Day,

November 11, Veterans' Day,

Fourth Thursday in November, Thanksgiving Day, and

December 25, Christmas Day.

In the case of any statement or other document required to be filed, or any other act required under the authority of provisions of 26 U.S.C. enforced and administered by the Bureau to be performed at any office of the Bureau or any other office or agency of the United States, located outside the District of Columbia, the term “legal holiday” includes, in addition to the legal holidays enumerated in paragraph (b)(1) of this section, any statewide legal holiday of the State where the act is required to be performed. If the act is performed in accordance with law at an office of the Bureau or any other office or agency of the United States located in a Territory or possession of the United States, the term “legal holiday” includes, in addition to the legal holidays described in paragraph (b)(1) of this section, any legal holiday which is recognized throughout the Territory or possession in which the office is located.