Section 25.2505-1 - Unified credit against gift tax; in general(a)General rule. Section 2505(a) allows a citizen or resident of the United States a credit against the tax imposed by section 2501 for each calendar year. The allowable credit is the applicable credit amount in effect under section 2010(c) that would apply if the donor died as of the end of the calendar year, reduced by the sum of the amounts allowable as a credit against the gift tax due for all preceding calendar periods. See §§ 25.2505-2 , 20.2010-1 , and 20.2010-2 for additional rules and definitions related to determining the applicable credit amount in effect under section 2010(c).(b)Applicable rate of tax. In determining the amounts allowable as a credit against the gift tax due for all preceding calendar periods, the unified rate schedule under section 2001(c) in effect for such calendar year applies instead of the rates of tax actually in effect for preceding calendar periods. See sections 2505(a) and 2502(a)(2).(c)Special rule in case of certain gifts made before 1977. The applicable credit amount allowable under paragraph (a) of this section must be reduced by an amount equal to 20 percent of the aggregate amount allowed as a specific exemption under section 2521 (as in effect before its repeal by the Tax Reform Act of 1976) for gifts made by the decedent after September 8, 1976, and before January 1, 1977.(d)Credit limitation. The applicable credit amount allowed under paragraph (a) of this section for any calendar year shall not exceed the amount of the tax imposed by section 2501 for such calendar year.(e)Effective/applicability date. This section applies to gifts made on or after June 12, 2015. See 26 CFR 25.2505-1 T, as contained in 26 CFR part 25 , revised as of April 1, 2015, for the rules applicable to gifts made on or after January 1, 2011, and before June 12, 2015.T.D. 9725, 80 FR 34290, June 16, 2015