Alternative Minimum Tax (AMT) Calculator 2026
Find out if you owe AMT and calculate the exact amount.
Regular Tax Info
AMT Preference Items
AMT Owed
$994
Total tax: $45,994 · Effective AMT rate: 0.38%
AMT Calculation Breakdown
AMT Basics
- AMT rates: 26% up to the threshold, 28% above.
- Common triggers: large ISO exercises, high SALT deductions, private activity bonds.
- AMT paid may generate a credit usable in future years (Form 8801).
What Is the Alternative Minimum Tax?
The Alternative Minimum Tax is a parallel tax system originally designed to prevent wealthy taxpayers from using deductions and credits to pay zero federal tax. It recalculates your tax liability by adding back certain "preference items" — deductions that reduce your regular tax but aren't allowed under AMT. If the AMT calculation produces a higher tax than your regular tax, you pay the difference as additional tax.
After the Tax Cuts and Jobs Act (TCJA) of 2017, the number of taxpayers subject to AMT dropped dramatically — from about 5 million to fewer than 200,000. The TCJA nearly doubled the AMT exemption and significantly raised the phase-out threshold. However, if TCJA provisions sunset after 2025, millions could face AMT again.
2026 AMT Exemption Amounts
| Filing Status | Exemption | Phase-Out Begins |
|---|---|---|
| Single / HOH | $88,100 | $609,350 |
| Married Filing Jointly | $137,000 | $1,218,700 |
| Married Filing Separately | $68,500 | $609,350 |
The exemption reduces dollar-for-dollar as AMT income (AMTI) rises above the phase-out threshold, at a rate of 25 cents per dollar. This means the exemption is fully eliminated once AMTI exceeds the threshold by four times the exemption amount.
Common AMT Triggers
- Incentive Stock Options (ISOs) — The "bargain element" (market price minus exercise price) at exercise is not taxed for regular income tax purposes but is added to AMTI. A large ISO exercise can trigger tens or hundreds of thousands in AMT.
- State and Local Tax (SALT) deductions above $10,000 — Under TCJA, SALT is capped at $10,000 for regular tax. Before TCJA (and potentially after sunset), the excess SALT deduction is an AMT preference item.
- Private activity bond interest — Interest from certain municipal bonds that fund private projects is tax-free for regular tax but taxable for AMT.
- Accelerated depreciation — The difference between accelerated and straight-line depreciation on certain property is an AMT adjustment.
AMT Tax Rates
The AMT uses a two-bracket system: 26% on the first $232,600 of AMT base (for single filers; $116,300 for MFS) and 28% on amounts above that threshold. Long-term capital gains and qualified dividends are taxed at their preferential rates (0%/15%/20%) under both the regular and AMT systems.
AMT Credit Carryforward
If you pay AMT due to "deferral" items like ISO exercises (as opposed to "exclusion" items like SALT), you can claim an AMT credit (Form 8801) in future years to offset regular tax. This credit carries forward indefinitely, so you eventually recover the AMT paid — though the time value of money means you still incur a real cost.
Frequently Asked Questions
How do I know if I owe AMT?
You're most likely to owe AMT if you exercised incentive stock options, have large SALT deductions (especially if TCJA sunsets), or receive private activity bond interest. IRS Form 6251 walks through the calculation. Most tax software flags AMT automatically.
Can I avoid AMT when exercising ISOs?
You can reduce AMT exposure by spreading ISO exercises across multiple tax years, exercising only enough shares to stay below the AMT exemption threshold, or exercising and selling in the same calendar year (which converts the gain to regular income rather than an AMT preference item).