AMT Calculator 2025 β Alternative Minimum Tax Estimator
Calculate whether you owe Alternative Minimum Tax in 2025. Enter your taxable income, ISO exercises, and preference items to see your AMT liability.
$
After standard/itemized deduction $
From your federal income tax calculation $
FMV minus strike price Γ shares exercised $
Disallowed for AMT purposes $
Excess depreciation over ADS method $
Private activity bond interest, etc. $0
Additional AMT Owed
$0
Tentative Minimum Tax
$0
AMT Exemption
$0
Alternative Minimum Income
AMT Calculation Worksheet
How to Use This AMT Calculator
Enter your regular taxable income and regular federal tax. Then add any AMT preference items β most importantly ISO exercise spreads (the most common AMT trigger for tech workers) and state taxes you deducted (not allowed under AMT).
The Formula
AMTI = Regular Taxable Income + ISO Spread + SALT + Depreciation + Other Preferences
AMT Exemption = $88,100 (single) / $137,000 (married) β phases out above threshold
AMT Base = max(0, AMTI β AMT Exemption)
Tentative Min Tax = 26% Γ min(AMTI, $248,300) + 28% Γ max(0, AMTI β $248,300)
AMT Owed = max(0, Tentative Min Tax β Regular Tax)
AMT Exemption = $88,100 (single) / $137,000 (married) β phases out above threshold
AMT Base = max(0, AMTI β AMT Exemption)
Tentative Min Tax = 26% Γ min(AMTI, $248,300) + 28% Γ max(0, AMTI β $248,300)
AMT Owed = max(0, Tentative Min Tax β Regular Tax)
Example
Single, $200K regular taxable income, $150K ISO exercise:
AMTI = $200,000 + $150,000 + $10,000 SALT = $360,000
AMT Exemption: $88,100 (no phase-out at this income)
AMT Base: $360,000 β $88,100 = $271,900
Tentative Min Tax: $248,300 Γ 26% + $23,600 Γ 28% = $71,246
Regular Tax: $38,000
AMT Owed: $33,246
AMTI = $200,000 + $150,000 + $10,000 SALT = $360,000
AMT Exemption: $88,100 (no phase-out at this income)
AMT Base: $360,000 β $88,100 = $271,900
Tentative Min Tax: $248,300 Γ 26% + $23,600 Γ 28% = $71,246
Regular Tax: $38,000
AMT Owed: $33,246
Extended
AMT Trigger Analysis
Understand what triggers AMT and strategies to minimize it
AMT Trigger Analysis & Planning Strategies
Your AMT Risk Factors
ISO Exercise AMT Planning
- Exercise ISOs in small batches over multiple years to keep AMTI below the exemption phase-out range
- Disqualifying dispositions: Selling ISO shares in the same year you exercise avoids AMT (but creates ordinary income)
- AMT credit: AMT paid due to ISO exercises can be recovered in future years via the Minimum Tax Credit (Form 8801)
- Year-end planning: Model AMT before December 31 to decide how many ISOs to exercise
- Hold period: To get long-term capital gains treatment AND avoid AMT in the sale year, you must hold ISOs for 2+ years from grant and 1+ year from exercise
AMT-Free Zone Strategies
- Keep AMTI below exemption amount ($88,100 single / $137,000 married)
- State taxes (SALT) are disallowed for AMT β if SALT is your main deduction, AMT may not affect you much after the $10K cap
- Traditional 401(k) contributions reduce AMTI
- HSA contributions reduce AMTI
- Municipal bonds: avoid private activity bonds, which generate AMT income
2025 AMT Key Numbers
| Item | Single | Married Filing Jointly |
|---|---|---|
| AMT Exemption | $88,100 | $137,000 |
| Exemption Phase-Out Begins | $626,350 | $1,252,700 |
| Exemption Fully Phased Out | $978,750 | $1,800,700 |
| AMT Rate (up to $248,300) | 26% | 26% |
| AMT Rate (above $248,300) | 28% | 28% |
Frequently Asked Questions
What is the Alternative Minimum Tax (AMT)?
The AMT is a parallel tax system that ensures high-income taxpayers pay at least a minimum amount of federal income tax, even with extensive deductions. You calculate your tax both ways and pay whichever is higher. The AMT disallows many regular deductions like SALT and personal exemptions.
Who typically pays the AMT?
The AMT primarily affects taxpayers with income between $200,000 and $1,000,000 who exercise incentive stock options (ISOs), have large SALT deductions, claim accelerated depreciation, or have significant miscellaneous deductions. The exemption amounts protect most middle-income taxpayers.
What is the AMT exemption for 2025?
The 2025 AMT exemption is $88,100 for single filers and $137,000 for married filing jointly. This exemption phases out at $626,350 (single) and $1,252,700 (married), reducing by $0.25 for every $1 above the phase-out threshold.
What income triggers the AMT?
Common AMT triggers include: exercising Incentive Stock Options (ISOs), large state and local tax deductions (which are disallowed for AMT), accelerated depreciation deductions, and tax-exempt interest from certain private activity bonds. Being in the 28% AMT bracket (above $248,300) rather than the regular 22-24% bracket can also trigger it.
Is there an AMT credit?
Yes, if you pay AMT in one year due to timing differences (not permanent differences), you may receive a Minimum Tax Credit (MTC) that can offset regular tax in future years when you no longer owe AMT. This commonly happens with ISO exercises β the AMT you paid when exercising can be credited back when you sell the stock.