(a) The exclusive remedy of a taxpayer with respect to the refund of monies paid in connection with a return filed under this chapter shall be the petition for refund provided under section 5884 of this title, and the appeal from an adverse determination of the petition for refund provided under section 5885 of this title. The exclusive remedy of a taxpayer with respect to a notification of deficiency or assessment of penalty or interest under sections 3202 and 3203 of this title shall be the petition for determination of the deficiency or assessment provided under section 5883 of this title, and the appeal from an adverse determination of deficiency or assessment provided under section 5885 of this title.

(b) Upon the failure of a taxpayer to petition in accordance with section 5883 of this title from a notice of deficiency or assessment under sections 3202 and 3203 of this title, or to appeal in accordance with section 5885 of this title from a determination of a deficiency or assessment of tax liability under section 5883 of this title, the taxpayer shall be bound by the terms of the notification, assessment, or determination, as the case may be. The taxpayer shall not thereafter contest, either directly or indirectly, the tax liability as therein set forth, in any proceeding, including a proceeding upon a claim of refund of all or any part of any payment made with respect to the tax liability, or a proceeding for the enforcement or collection of all or any part of the tax liability.

(c) Notwithstanding subsections (a) and (b) of this section, the Commissioner may compromise a tax liability arising under this title upon the grounds of doubt as to liability or doubt as to collectibility, or both. Upon acceptance by the Commissioner of an offer in compromise, the liability of the taxpayer in question is conclusively settled, and neither the taxpayer nor the Commissioner may reopen the case except by reason of falsification or concealment of assets by the taxpayer or mutual mistake of a material fact or if, in the opinion of the Commissioner, justice requires it. The decision of the Commissioner to reject an offer in compromise is not subject to review. The Commissioner may adopt rules regarding the procedures to be followed for the submission and consideration of offers in compromise. (Added 1966, No. 61 (Sp. Sess.), § 1, eff. Jan. 1, 1966; amended 2011, No. 45, § 36f, eff. May 24, 2011; 2017, No. 74, § 139.)