27 CFR 70.224 - Collection after assessment.
(a)Length of period -
(1)General rule. In any case in which a tax has been assessed within the statutory period of limitation properly applicable thereto, a proceeding in court to collect such tax may be begun, or levy for the collection of such tax may be made, within 10 years after the assessment thereof.
(2)Extension by agreement.
(i) The 10-year period of limitation on collection after assessment of any tax may, prior to the expiration thereof, be extended for any period of time agreed upon in writing by the taxpayer and the appropriate TTB officer. Whenever necessary to protect the revenue, such officer may also execute a written agreement with the taxpayer to extend the period of limitation. The extension becomes effective upon execution of the agreement by both the taxpayer and such officer.
(ii) The period of limitation on collection after assessment of any tax (including any extension of such period) may be extended after the expiration thereof if there has been a levy on any part of the taxpayer's property prior to such expiration and if the extension is agreed upon in writing prior to a release of the levy under the provisions of 26 U.S.C. 6343. An extension under this paragraph has the same effect as an agreement made prior to the expiration of the period of limitation on collection after assessment, and during the period of the extension collection may be enforced as to all property or rights to property owned by the taxpayer whether or not seized under the levy which was released.
(iii) Any period agreed upon under the provisions of paragraph (a)(1) of this section may be extended by subsequent agreements in writing made before the expiration of the period previously agreed upon.
(3) If a timely proceeding in court for the collection of a tax is commenced, the period during which such tax may be collected by levy shall be extended and shall not expire until the liability for the tax (or a judgment against the taxpayer arising from such liability) is satisfied or becomes unenforceable.