Alternative Minimum Tax
Parallel tax calculation ensuring high-income taxpayers pay a minimum federal tax regardless of deductions.
The Alternative Minimum Tax (AMT) is a parallel federal income tax system in the United States designed to ensure that high-income individuals and corporations pay at least a minimum amount of tax, regardless of deductions, credits, and preferences that reduce regular taxable income. Congress enacted the AMT in 1969 after discovering that 155 high-income households paid zero federal income tax by leveraging legal deductions.
For individual taxpayers, the AMT requires calculating income under an alternative set of rules—adding back certain 'preference items' (such as the spread on incentive stock option exercises, accelerated depreciation differences, and certain itemized deductions) to arrive at Alternative Minimum Taxable Income (AMTI). Taxpayers subtract an AMT exemption and apply flat AMT rates of 26% and 28% to the result. If the AMT liability exceeds regular tax liability, the difference is owed as AMT.
The Tax Cuts and Jobs Act of 2017 significantly raised AMT exemption amounts and phase-out thresholds, dramatically reducing the number of individual taxpayers subject to AMT. However, it remains highly relevant for employees with significant incentive stock option (ISO) grants—exercising ISOs triggers AMT preference income even if the underlying stock is not sold.
For corporations, the Inflation Reduction Act of 2022 created a 15% Corporate Alternative Minimum Tax (CAMT) on 'book income' (financial statement income) for large corporations with average adjusted financial statement income exceeding $1 billion.
Tax professionals advise clients to model AMT exposure before exercising ISOs, selling appreciated assets, or claiming large deductions to avoid unexpected tax bills.
FAQs
Who is most likely to owe AMT?
After the 2017 Tax Cuts and Jobs Act raised exemption thresholds, AMT primarily affects high-income individuals with large incentive stock option exercises, taxpayers in high-state-income-tax states who previously benefited from large SALT deductions, and individuals with significant accelerated depreciation deductions from real estate or business assets. The most common AMT trigger for tech employees is exercising incentive stock options (ISOs), where the spread between exercise price and fair market value creates AMT income even without a stock sale.
Can AMT paid be recovered in future years?
Yes—AMT paid creates an AMT credit (the Minimum Tax Credit or MTC) that can be applied against regular tax in future years when your regular tax liability exceeds your AMT liability. This credit can be carried forward indefinitely. For taxpayers who exercise ISOs and trigger AMT, selling the stock in a subsequent year (especially at a loss) can generate regular tax losses that create an opportunity to reclaim accumulated AMT credits, potentially recovering significant amounts over time.
How does AMT affect incentive stock option (ISO) planning?
When employees exercise ISOs, the spread between the exercise price and fair market value is not taxable under regular tax rules but is an AMT preference item. If the spread is large, it can trigger significant AMT. Planning strategies include spreading ISO exercises over multiple years to stay below the AMT threshold, exercising early in the year to know the tax liability before year-end, running AMT projections before any exercise, considering immediate disqualifying dispositions when stock values are low, and timing ISO exercises in years when regular income is lower.
Related Terms
Qualified Opportunity Zone
IRS-designated economically distressed area offering capital gains tax deferral and reduction for long-term investments.
Like-Kind Exchange
Tax-deferred swap of investment real estate for similar property under IRS Section 1031.
Section 179 Deduction
Immediate expensing of qualifying business property rather than depreciating it over multiple years.
Qualified Business Income Deduction
20% deduction for pass-through business income under IRC Section 199A for eligible self-employed taxpayers.
