2021 AMT Exemption
For 2021, the AMT Exemption is $114,600 (Exemption, joint returns or surviving spouses), $73,600 (Exemption, unmarried individuals), $57,300 (Exemption, married individuals filing separate returns) and 2 more figures below.
| Item | Joint returns or surviving spouses | Unmarried individuals | Married individuals filing separate returns | Estates and trusts |
|---|---|---|---|---|
| Exemption | $114,600 | $73,600 | $57,300 | $25,700 |
| Exemption phaseout threshold | $1,047,200 | - | - | - |
A dash is a figure this site has not published for that row, not an amount of zero.
Effective 2021-01-01Source: Rev. Proc. 2020-45 (IRS)Verified 2026-08-29
Compared with 2020
| Item | 2020 | 2021 | Change |
|---|---|---|---|
| Exemption, joint returns or surviving spouses | $113,400 | $114,600 | +$1,200 (+1.1%) |
| Exemption, unmarried individuals | $72,900 | $73,600 | +$700 (+1.0%) |
| Exemption, married individuals filing separate returns | $56,700 | $57,300 | +$600 (+1.1%) |
| Exemption, estates and trusts | $25,400 | $25,700 | +$300 (+1.2%) |
| Exemption phaseout threshold, joint returns or surviving spouses | $1,036,800 | $1,047,200 | +$10,400 (+1.0%) |
Who it applies to
Taxpayers subject to the Alternative Minimum Tax, including individuals filing joint returns, unmarried individuals, married individuals filing separate returns, and estates and trusts.
What changed this year, and why
For taxable years beginning in 2021, the IRS published updated Alternative Minimum Tax (AMT) exemption amounts and phaseout thresholds under IRC § 55.
Common questions
- What is the AMT exemption amount for each filing status in 2021?
- For joint returns or surviving spouses the exemption is $114,600. For unmarried individuals it is $73,600. For married individuals filing separate returns it is $57,300. For estates and trusts it is $25,700.
- At what income level does the AMT exemption begin to phase out for joint filers?
- For joint returns or surviving spouses, the exemption begins to phase out when alternative minimum taxable income exceeds $1,047,200.
What the alternative minimum tax actually is
The alternative minimum tax (AMT) is a parallel tax system that runs alongside the regular income tax. It targets taxpayers who benefit from certain preferential tax treatment - such as favorable income classifications or special deductions - that might otherwise allow them to pay little or no federal income tax despite having substantial economic income. Rather than eliminating these tax benefits entirely, the AMT places a floor on how much they can reduce a taxpayer's overall liability. Taxpayers compute their tax under both the regular system and the AMT system, and owe the higher of the two amounts. The AMT has its own set of rules for what counts as income, what deductions are allowed, and what rates apply, which can differ significantly from regular tax treatment.
The AMT is a separate tax that is imposed in addition to your regular tax. It applies to taxpayers who have certain types of income that receive favorable treatment, or who qualify for certain deductions, under the tax law. These tax benefits can significantly reduce the regular tax of some taxpayers with higher economic incomes. The AMT sets a limit on the amount these benefits can be used to reduce total tax.
Instructions for Form 6251 (2021), Alternative Minimum Tax - Individuals (IRS)
When you have to file Form 6251
Taxpayers must attach Form 6251 to their return if any of four conditions apply. First, file if line 7 (tentative minimum tax before credits) exceeds line 10, meaning the AMT calculation produces a positive amount after comparing against regular tax. Second, file if you claim a general business credit and either Part I line 6 or line 25 of Form 3800 is more than zero. Third, file if you claim certain specific credits: the qualified electric vehicle credit (Form 8834), the personal-use portion of the alternative fuel vehicle refueling property credit (Form 8911), or the credit for prior-year minimum tax (Form 8801). Fourth, file if the total of Form 6251 lines 2c through 3 is negative and line 7 would exceed line 10 without taking those lines into account. Meeting any one of these triggers requires filing the form.
Who Must File Attach Form 6251 to your return if any of the following statements are true. 1. Form 6251, line 7, is greater than line 10. 2. You claim any general business credit, and either line 6 (in Part I) of Form 3800 or line 25 of Form 3800 is more than zero. 3. You claim the qualified electric vehicle credit (Form 8834), the personal use part of the alternative fuel vehicle refueling property credit (Form 8911), or the credit for prior year minimum tax (Form 8801). 4. The total of Form 6251, lines 2c through 3, is negative and line 7 would be greater than line 10 if you didn’t take into account lines 2c through 3.
Instructions for Form 6251 (2021), Alternative Minimum Tax - Individuals (IRS)
How the exemption is taken away as income rises
The AMT exemption is reduced when a taxpayer's alternative minimum taxable income (AMTI) exceeds a phase-out threshold. Once AMTI reaches that threshold, the exemption is gradually eliminated. For 2021, if single or head of household, the exemption reaches zero when AMTI hits $818,000. If married filing jointly or a qualifying widow(er), the exemption is zero when AMTI equals or exceeds $1,505,600. If married filing separately, the exemption is zero at $752,800. Taxpayers whose AMTI equals or exceeds these upper amounts enter zero on the exemption line and skip the worksheet entirely. Those with AMTI below the zero-exemption point but above the phase-out threshold must complete the Exemption Worksheet to determine their reduced exemption amount. The verified phase-out threshold for joint returns or surviving spouses is $1,047,200, meaning the exemption begins shrinking once income passes that level.
Note. If Form 6251, line 4, is equal to or more than: $818,000 if single or head of household, $1,505,600 if married filing jointly or qualifying widow(er), or $752,800 if married filing separately, your exemption is zero. Don’t complete this worksheet; instead, enter the amount from Form 6251, line 4, on line 6 and go to line 7.
Instructions for Form 6251 (2021), Alternative Minimum Tax - Individuals (IRS)
The two AMT rates and where the second one starts
The AMT uses two rates: a 26% rate that applies to lower amounts of taxable excess, and a 28% rate that applies once taxable excess crosses a threshold. For 2021, the 26% rate applies to the first $199,900 of taxable excess ($99,950 if married filing separately). Any taxable excess above that threshold is taxed at 28%. The computation applies the 28% rate to the entire taxable excess amount and then subtracts a fixed dollar amount to adjust for the difference: subtract $3,998 if single or married filing jointly ($1,999 if married filing separately). This structure ensures the marginal rate on amounts above the threshold is effectively 28%, while income below the threshold is taxed at 26%. The taxable excess amount appears on Form 6251, line 6, and the computed tax goes on line 7.
All other Form 1040-NR filers, don’t complete Part III. Instead, if Form 6251, line 6, is $199,900 or less ($99,950 or less if married filing separately), figure the amount to enter on line 7 by multiplying line 6 by 26% (0.26). Otherwise, figure the amount to enter on line 7 by multiplying line 6 by 28% (0.28) and subtracting $3,998 ($1,999 if married filing separately) from the result.
Instructions for Form 6251 (2021), Alternative Minimum Tax - Individuals (IRS)
How each figure was verified
Each number below was read from a stored copy of the document named beside it, and checked to occur word for word in the quoted sentence. The digest is of that stored text.
Rev. Proc. 2020-45 (IRS)
- Exemption, joint returns or surviving spouses
Joint Returns or Surviving Spouses $114,600
- Exemption, unmarried individuals
Unmarried Individuals (other than Surviving Spouses) $73,600
- Exemption, married individuals filing separate returns
Married Individuals Filing Separate Returns $57,300
- Exemption, estates and trusts
Estates and Trusts $25,700
- Exemption phaseout threshold, joint returns or surviving spouses
For taxable years beginning in 2021, the amounts used under § 55(d)(2) to determine the phaseout of the exemption amounts are: Threshold Complete Phaseout amount Phaseout amount Joint Returns or Surviving Spouses $1,047,200 $1,505,600