Section 21-J:29 - Statute of Limitations; ExceptionsI.(a) Except as otherwise provided, all taxes administered by the department shall be assessed within 3 years after the return is filed or within 3 years after the last day prescribed by law for filing such return, whichever is later, or in the event no return is required, within 3 years from the date the tax is due or paid, whichever is later. In the case in which a return is required, the 3-year period shall commence with the filing of an original return and shall not be affected by the filing of an amended return.(b) Except as otherwise provided, any claim for a refund or credit shall be made within 3 years from the due date of the tax upon which such refund is claimed or within 2 years from the date the tax was paid, whichever is later.(c) Notwithstanding subparagraph I(b), any claim for a refund or credit of taxes, penalties or interest paid as a result of an assessment or demand for payment shall be made within 3 years of the due date of the tax upon which such refund is claimed.(d) Notwithstanding subparagraphs I(b) and (c), any claim for a refund or credit of taxes based upon a claim that the tax or any provision thereof is unconstitutional under the federal or state constitution shall be made within 120 days of the due date of the tax upon which such refund is claimed.(e) Notwithstanding subparagraphs I(b), (c), and (d), in the case of a petition for refund of overpayment of taxes based upon a claim of a fraudulent investment scheme under RSA 21-J:28-e, the petition for a refund shall be made within 180 days of the taxpayer filing an amended federal tax return claiming a theft loss for the fraudulent investment scheme under Internal Revenue Code section 165.II.(a) In the case of any failure to make or file a return or declaration of consideration for any tax administered by the department, the tax may be assessed at any time.(b) In the case of a willful attempt in any manner to evade any tax administered by the department the tax may be assessed at any time.(c) If a taxpayer omits from gross income or gross business profits an amount properly includable therein which is in excess of 25 percent of the amount of gross income or gross business profits stated in the return or understates the value of consideration for the transfer of real property in an amount which is in excess of 25 percent of the total consideration for such transfer, the department may assess the tax at any time within 6 years after the return or declaration of consideration was filed.III. With respect to any tax to which the limitation period provided in paragraph I or subparagraph II(c) shall apply and such period has not expired, the commissioner and the taxpayer may, in writing, agree to extend such period.IV. Where the assessment of any tax administered by the department has been made within the applicable period of limitation, such tax may be collected by lien or by a proceeding in court, but only if the lien is made or the proceeding commenced within 12 years of the assessment of the tax.Amended by 2012, 154:2, eff. 6/7/2012.1985, 204:1. 1991, 163:6. 1994, 326:2, 3. 2007, 150:4, eff. Aug. 17, 2007. 2012, 154:2, eff. June 7, 2012.