The Tax Reform Act of 1976, referred to in subsec. (b), is Pub. L. 94–455, Oct. 4, 1976, 90 Stat. 1520, as amended. For complete classification of this Act to the Code, see Tables.

Section 2521 of this title, referred to in subsec. (b), was repealed by section 2001(b)(3) of Pub. L. 94–455, applicable to gifts made after Dec. 31, 1976.

2001—Subsec. (c). Pub. L. 107–16, §§ 521(a), 901, in table, temporarily substituted provision that in the case of estates of decedents dying during the years 2002 and 2003, the years 2004 and 2005, the years 2006, 2007, and 2008, and the year 2009, the applicable exclusion amount is $1,000,000, $1,500,000, $2,000,000, and $3,500,000, respectively, for provision that in the case of decedents dying, and gifts made, during the year 1998, the year 1999, the years 2000 and 2001, the years 2002 and 2003, the year 2004, the year 2005, and the year 2006 or thereafter, the applicable exclusion amount is $625,000, $650,000, $675,000, $700,000, $850,000, $950,000, and $1,000,000, respectively. See Effective and Termination Dates of 2001 Amendment note below.

1997—Subsec. (a). Pub. L. 105–34, § 501(a)(1)(A), substituted “the applicable credit amount” for “$192,800”.

Subsecs. (c), (d). Pub. L. 105–34, § 501(a)(1)(B), added subsec. (c) and redesignated former subsec. (c) as (d).

1990—Subsecs. (b) to (d). Pub. L. 101–508 redesignated subsecs. (c) and (d) as (b) and (c), respectively, and struck out former subsec. (b) which provided for a phase-in of the unified credit against estate tax.

1981—Subsec. (a). Pub. L. 97–34, § 401(a)(1), substituted “$192,800” for “$47,000”.

Subsec. (b). Pub. L. 97–34, § 401(a)(2)(A), struck out “$47,000” before “credit” from heading and in text substituted in subsec. (a) substitutions for “$192,800” amounts of “$62,800”, “$79,300”, “$96,300”, “$121,800”, and “$155,800” in the case of decedents dying in 1982, 1983, 1984, 1985, and 1986, respectively, for subsec. (a) substitutions for “$47,000” amounts of “$30,000”, “$34,000”, “$38,000”, and “$42,500” in the case of decedents dying in 1977, 1978, 1979, and 1980, respectively.

Pub. L. 107–16, title V, § 521(e), June 7, 2001, 115 Stat. 72, provided that:

“(1) In general.—Except as provided in paragraphs (2) and (3), the amendments made by this section [amending this section and sections 2057, 2505, and 2631 of this title] shall apply to estates of decedents dying, and gifts made, after December 31, 2001.

“(2) Subsection (b)(2).—The amendments made by subsection (b)(2) [amending section 2505 of this title] shall apply to gifts made after December 31, 2009.

“(3) Subsections (c) and (d).—The amendments made by subsections (c) and (d) [amending sections 2057 and 2631 of this title] shall apply to estates of decedents dying, and generation-skipping transfers, after December 31, 2003.”

Amendment by Pub. L. 107–16 inapplicable to estates of decedents dying, gifts made, or generation skipping transfers, after Dec. 31, 2010, and the Internal Revenue Code of 1986 to be applied and administered to such estates, gifts, and transfers as if such amendment had never been enacted, see section 901 of Pub. L. 107–16, set out as a note under section 1 of this title.

Amendment by Pub. L. 105–34 applicable to estates of decedents dying, and gifts made, after Dec. 31, 1997, see section 501(f) of Pub. L. 105–34, set out as a note under section 2001 of this title.

Section 401(c)(1) of Pub. L. 97–34 provided that: “The amendments made by subsection (a) [amending this section and section 6018 of this title] shall apply to the estates of decedents dying after December 31, 1981”.

For provisions that nothing in amendment by Pub. L. 101–508 be construed to affect treatment of certain transactions occurring, property acquired, or items of income, loss, deduction, or credit taken into account prior to Nov. 5, 1990, for purposes of determining liability for tax for periods ending after Nov. 5, 1990, see section 11821(b) of Pub. L. 101–508, set out as a note under section 45K of this title.