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    Alternative Minimum Tax (AMT)

    The AMT is a parallel tax: you recompute your income by adding back preference items (like private-activity bond interest and the ISO bargain element), subtract a flat exemption ($90,100 single / $140,200 MFJ for 2026), and apply 26% on the first $248,300 of AMT base and 28% above. You pay the AMT only if it exceeds your regular tax. The big 2026 change from OBBBA: the exemption now phases out at 50% (up from 25%) once income exceeds $500,000 (single) or $1,000,000 (MFJ), so it vanishes faster and catches more high earners. AMT from timing items (ISOs, depreciation) generates a credit on Form 8801 you can recover in later years; AMT from exclusion items (PAB interest, the old SALT add-back) does not.

    TaxKiln Editorial · Last reviewed:

    The Alternative Minimum Tax (AMT) is a second, parallel federal income tax. You compute your tax the normal way, then recompute it under the AMT rules -- adding back certain deductions and tax breaks, subtracting a flat exemption, and applying a 26% or 28% rate -- and you pay whichever is higher. For most of the last decade almost nobody paid AMT: the 2017 TCJA raised the exemption and phase-out thresholds so high that the tax went dormant for the middle class. But that is changing in 2026. OBBBA kept the higher exemption yet reset the phase-out to start at lower income ($500,000 single / $1,000,000 married) and doubled the phase-out rate from 25% to 50%. The practical effect is that the exemption now disappears twice as fast for high earners, and more people -- especially those exercising incentive stock options, holding private-activity municipal bonds, or recognizing large one-time gains -- will owe AMT again. This guide explains the mechanics, the 2026 numbers, and the levers that matter. For the equity-compensation angle in depth, see the ISO Tax Guide.

    Key mechanics

    What the AMT is, and why it is coming back in 2026

    The AMT under IRC Section 55 is a separate tax system that runs alongside the regular income tax. The idea, dating to 1969, was to stop high-income taxpayers from stacking enough deductions and preferences to pay little or no tax. You calculate your regular tax, then calculate a "tentative minimum tax" under the AMT rules, and you owe the regular tax plus any amount by which the tentative minimum tax exceeds it.

    For most of the post-2017 period the AMT was effectively dormant for ordinary filers. The TCJA sharply raised both the exemption and the income level at which it begins to phase out, and the $10,000 SALT cap removed what had historically been the single biggest AMT trigger (large state-tax deductions). The number of people paying AMT fell by roughly 95%.

    OBBBA changes the picture for 2026. It made the higher exemption permanent, but it reset the phase-out to begin at lower income -- $500,000 (single) and $1,000,000 (married filing jointly) -- and it doubled the phase-out rate from 25 cents to 50 cents per dollar of income above those thresholds. The exemption therefore erodes twice as fast, and the income band over which high earners lose it is both lower and narrower. Combined with the SALT cap itself reverting to $10,000 in 2030, the AMT is structurally on its way back as a tax that upper-middle and high earners must actually check, not assume away.

    The AMT is a parallel tax: you pay your regular tax plus any excess of the tentative minimum tax over it. OBBBA kept the higher exemption but, for 2026, lowered the phase-out thresholds to $500,000/$1,000,000 and doubled the phase-out rate to 50%, expanding who owes it. (IRC §55 (alternative minimum tax imposed); IRC §55(d) (exemption and phase-out); OBBBA 2026 phase-out thresholds $500,000 (single) / $1,000,000 (MFJ) at 50%)

    The 2026 numbers: exemption, the new 50% phase-out, and the rate brackets

    For tax year 2026 the AMT exemption amounts (inflation-indexed under Rev. Proc. 2025-32) are $90,100 for single filers and $140,200 for married filing jointly ($70,100 for married filing separately). The AMT rate is 26% on the AMT base up to $248,300, and 28% on the amount above $248,300 (this $248,300 breakpoint is also indexed).

    The phase-out is where 2026 bites. The exemption is reduced by 50 cents for every dollar of alternative minimum taxable income (AMTI) above the threshold -- $500,000 for single filers, $1,000,000 for joint filers. At a 50% rate, a single filer's $90,100 exemption is fully gone by $680,200 of AMTI, and a joint filer's $140,200 exemption is fully gone by $1,280,400. Within the phase-out band, the lost exemption creates a "stealth" marginal rate: each extra dollar of AMTI both is taxed and removes 50 cents of exemption that is then also taxed, pushing the effective AMT rate above the nominal 28%.

    To see the OBBBA difference concretely: a married couple with $1,100,000 of AMTI in 2026 is $100,000 over the threshold. At the new 50% rate, their $140,200 exemption is cut by $50,000 to $90,200. Under the old 25% rate the cut would have been only $25,000. That doubling is the core reason more high earners will owe AMT in 2026 than in any year since 2017.

    For 2026 the AMT exemption is $90,100 (single) / $140,200 (MFJ), with a 26% rate up to $248,300 of AMT base and 28% above. The exemption phases out at 50% above $500,000 (single) / $1,000,000 (MFJ), fully gone at $680,200 / $1,280,400. (IRC §55(b)(1) (26%/28% rates); IRC §55(d)(3) (phase-out); 2026 amounts per Rev. Proc. 2025-32; $248,300 rate breakpoint (indexed))

    How AMTI is built: the preferences and adjustments you add back

    Alternative minimum taxable income starts from your regular taxable income and adds back items the AMT does not allow. The most common, under IRC Sections 56 and 57:

    - Private-activity bond interest (Section 57(a)(5)). Interest on certain "private activity" municipal bonds is tax-exempt for the regular tax but is a preference item added back for AMT. This catches investors who bought higher-yielding munis without checking whether they are AMT bonds. - The ISO bargain element (Section 56(b)(3)). When you exercise an incentive stock option and hold the shares, the spread between strike price and fair market value is added to AMTI even though it is invisible to the regular tax. This is the single most common AMT trigger for tech employees -- covered in depth in the ISO Tax Guide. - Depreciation differences (Section 56(a)(1)). Accelerated depreciation taken for the regular tax is recomputed using slower AMT methods, and the difference is added back. This affects business owners and real-estate investors who use bonus depreciation or shorter MACRS lives. - The standard deduction and certain itemized items. If you claim the standard deduction, it is added back for AMT. State and local tax deductions were historically the largest add-back, but the SALT cap has muted that until the cap reverts in 2030.

    The mechanic is always the same: regular taxable income, plus the add-backs, equals AMTI. Then subtract the (possibly phased-out) exemption to get the AMT base, apply 26%/28%, and compare to regular tax.

    AMTI equals regular taxable income plus add-backs: private-activity bond interest, the ISO bargain element, accelerated-depreciation differences, and (if claimed) the standard deduction. The SALT add-back is muted while the SALT cap applies. (IRC §56 (adjustments); IRC §57 (items of tax preference); IRC §56(b)(3) (ISO adjustment); IRC §57(a)(5) (private-activity bond interest))

    Capital gains and qualified dividends: preferential rate, but they still phase out your exemption

    A common misunderstanding is that a big capital gain "causes AMT." It is more subtle. Long-term capital gains and qualified dividends keep their preferential 0/15/20% rate inside the AMT calculation -- they are not taxed at 26% or 28%. So a large gain does not, by itself, generate AMT through a higher rate.

    What a large gain does do is raise your AMTI. And because AMTI is what drives the exemption phase-out, a big one-time gain can push you into or through the $500,000 / $1,000,000 phase-out band, stripping away your AMT exemption. The lost exemption then exposes more of your ordinary AMTI to the 26%/28% AMT rates. So the gain is not taxed at AMT rates, but it can cause your other income to be, by eliminating the shelter the exemption would otherwise provide.

    This is why a year with a large home sale, business sale, or concentrated-stock liquidation deserves an AMT projection even if the gain itself is "just" long-term. The interaction between a lumpy gain, the phase-out, and any preference items (PAB interest, an ISO exercise in the same year) is exactly the kind of stacking that produces a surprise AMT bill. Spreading large realizations across years -- installment sales, staged liquidity -- is a primary lever precisely because it keeps AMTI below the phase-out band.

    Long-term capital gains and qualified dividends keep their 0/15/20% rate inside the AMT, so they are not taxed at AMT rates. But they raise AMTI, which can phase out the AMT exemption and expose your other income to the 26%/28% AMT rate. (IRC §55(b)(3) (capital gains keep preferential rate for AMT); IRC §55(d)(3) (AMTI drives exemption phase-out))

    The AMT credit: timing items come back, exclusion items do not

    Not all AMT is permanent. The tax code distinguishes two kinds of AMT-causing items, and only one generates a credit you can recover later.

    Timing (deferral) items create a minimum tax credit. The classic example is the ISO bargain element: you pay AMT in the exercise year on a spread the regular tax has not yet recognized, but when you eventually sell the shares the regular tax catches up. Accelerated-depreciation add-backs are similar -- the difference reverses over the asset's life. AMT attributable to these timing items generates a minimum tax credit under IRC Section 53, carried forward indefinitely on Form 8801. In any later year where your regular tax exceeds your tentative minimum tax, you use the credit to recover the earlier AMT.

    Exclusion items do not generate a credit. AMT caused by private-activity bond interest, the standard deduction add-back, or the (currently muted) SALT add-back is permanent -- there is no future year in which the regular tax "catches up," so no credit arises. This money is simply gone.

    The practical upshot: AMT from an ISO exercise is often a prepayment of tax you would owe anyway, recoverable over time, which changes how you should think about the cash hit. AMT from muni-bond interest is a true added cost. Knowing which bucket your AMT falls into determines whether it is a timing inconvenience or a permanent leak.

    AMT from timing items (ISO bargain element, depreciation) generates a minimum tax credit (Form 8801) recoverable in later years when regular tax exceeds tentative minimum tax. AMT from exclusion items (PAB interest, standard deduction, SALT) is permanent and generates no credit. (IRC §53 (credit for prior year minimum tax); Form 8801; distinction between deferral and exclusion preferences)

    QSBS and the AMT: the §1202 exclusion works for both

    One of the most valuable interactions for founders and early employees is that the Qualified Small Business Stock exclusion under IRC Section 1202 applies for BOTH the regular tax and the AMT. Gain excluded under Section 1202 on the sale of qualifying QSBS (C-corporation stock, issued by a company with gross assets under the statutory cap, held for the required period) is not pulled back in as an AMT preference.

    This was not always the case. For older QSBS, a portion of the excluded gain was an AMT preference item, which clawed back some of the benefit. For QSBS acquired after the 2010 changes and excluded at the 100% rate, there is no AMT add-back -- the exclusion is clean for AMT purposes. OBBBA further expanded QSBS (higher gain caps and a tiered holding period), and the AMT-clean treatment continues to apply to the excluded gain.

    For a startup employee who early-exercises with a Section 83(b) election and holds for the QSBS period, the combination is powerful: the exercise can be timed to minimize the AMT bargain-element adjustment, and the eventual gain can be both excluded from regular tax under Section 1202 and free of any AMT preference add-back. See the ISO Tax Guide and the QSBS guide for the holding-period mechanics.

    Gain excluded under §1202 (Qualified Small Business Stock) is excluded for both regular tax and AMT -- 100%-excluded QSBS gain is not an AMT preference item, so the exclusion is not clawed back by the AMT. (IRC §1202 (QSBS exclusion); §1202(a)(4) and the post-2010 100% exclusion with no AMT preference; OBBBA QSBS expansion)

    Who actually needs to run Form 6251

    You compute the AMT on Form 6251 and report any AMT on Schedule 2. Tax software does this automatically, but the people most at risk of an unexpected bill -- and who should run a projection BEFORE year-end, not discover it at filing -- share clear profiles:

    - Anyone exercising and holding incentive stock options, especially pre-IPO shares where the fair-market-value spread is large. - Holders of private-activity municipal bonds (check whether your "tax-free" munis are AMT bonds; many higher-yield munis are). - Business owners and real-estate investors taking bonus depreciation or large Section 179 deductions, which create AMT depreciation add-backs. - High earners now in or above the $500,000 / $1,000,000 phase-out band, especially in a year with a large one-time capital gain that pushes AMTI through the band. - Filers with large families who lost personal exemptions but whose deduction profile still differs sharply between the two systems.

    The mistake is assuming the post-2017 "nobody pays AMT" reality still holds in 2026. With the lower phase-out thresholds and the doubled phase-out rate, the safest move for anyone with income near or above the thresholds, or with any of the preference items above, is to run a side-by-side Form 6251 projection before committing to a large exercise, sale, or depreciation election.

    AMT is computed on Form 6251 and reported on Schedule 2. The filers most at risk are ISO exercisers, private-activity-bond holders, business owners taking accelerated depreciation, and high earners in the phase-out band -- they should run a projection before year-end. (IRS Form 6251 (Alternative Minimum Tax -- Individuals); Schedule 2 (Form 1040); IRC §55)

    Planning levers that actually move the AMT

    Because the AMT turns on stacking and timing, the levers are mostly about WHEN income and preferences land:

    - Time and spread ISO exercises. Exercise in lower-income years and split exercises across calendar years to keep the annual bargain element below the level that triggers AMT or pushes you into the phase-out band. (See the ISO Tax Guide.) - Avoid stacking heavy events. Do not exercise ISOs, recognize a large capital gain, and do a big Roth conversion in the same year. Each raises AMTI; stacking them maximizes both the AMT rate exposure and the exemption phase-out. Sequence them across years. - Check your munis. If you hold private-activity bonds and AMT is a recurring problem, shifting to non-AMT municipal bonds removes a permanent (no-credit) preference item. - Mind the depreciation election. Bonus depreciation and Section 179 create AMT add-backs; in a borderline AMT year, electing slower depreciation for the regular tax can reduce the gap between the two systems. - Use the credit deliberately. After a year of timing-item AMT (ISOs, depreciation), watch for years in which your regular tax exceeds your tentative minimum tax and harvest the Form 8801 credit -- sometimes by accelerating ordinary income into such a year. - Watch the 2030 SALT reversion. When the SALT cap drops back to $10,000, the SALT add-back -- historically the biggest AMT driver -- partially returns to relevance for itemizers. Plan multi-year.

    The main AMT levers are timing-based: spread ISO exercises, avoid stacking large gains/conversions/exercises in one year, hold non-AMT munis, manage depreciation elections, and harvest the Form 8801 credit in years when regular tax exceeds tentative minimum tax. (IRC §56(b)(3) (ISO timing); IRC §53 (credit recovery); IRC §57(a)(5) (PAB interest); IRC §168 (depreciation methods))

    Action steps

    1. 1

      Run a Form 6251 projection before any large or lumpy event

      Before exercising ISOs, selling a business or property, doing a big Roth conversion, or claiming large bonus depreciation, run a side-by-side projection: regular tax versus tentative minimum tax. Estimate AMTI (regular taxable income plus your add-backs), subtract the 2026 exemption ($90,100 single / $140,200 MFJ, reduced 50% above $500,000 / $1,000,000), apply 26% up to $248,300 and 28% above, and compare to your regular tax. The excess of tentative minimum tax over regular tax is your AMT. Do this BEFORE the transaction, while you can still change the timing.

    2. 2

      Identify which preference items apply to you

      List your AMT add-backs: private-activity bond interest (check your 1099-INT box 13 and your bond documents), any ISO bargain element from exercises held past year-end, the difference between regular and AMT depreciation on business assets, and the standard deduction if you claim it. Separate them into timing items (ISO spread, depreciation -- recoverable via the Form 8801 credit) and exclusion items (PAB interest, standard deduction -- permanent). This tells you whether any AMT you owe is a prepayment or a true cost.

    3. 3

      Map your position against the $500,000 / $1,000,000 phase-out band

      Find where your projected AMTI sits relative to the 2026 phase-out start ($500,000 single / $1,000,000 MFJ) and the full-phase-out points ($680,200 / $1,280,400). If you are below the start, your full exemption is intact. If you are inside the band, every extra dollar of AMTI also strips 50 cents of exemption -- a stealth rate that makes lumpy income especially costly. A large one-time capital gain that pushes you into this band is the classic trap; model it specifically.

    4. 4

      Time and spread the items you control

      Spread ISO exercises across multiple years to keep each year's bargain element manageable. Do not stack an ISO exercise, a large capital gain, and a Roth conversion into the same year. Consider installment sales or staged liquidity for big gains to keep AMTI below the phase-out band. In a borderline year, weigh electing slower (regular) depreciation to shrink the gap between regular tax and tentative minimum tax. Sequencing across tax years is the single most effective AMT lever.

    5. 5

      Track and recover the minimum tax credit on Form 8801

      If you pay AMT on timing items (ISOs, depreciation), file Form 8801 every following year to compute and carry forward your minimum tax credit. The credit never expires. In any year your regular tax exceeds your tentative minimum tax, the credit offsets the difference -- recovering the earlier AMT. After an ISO qualifying disposition, when the gain is taxed as a long-term capital gain, your regular tax usually exceeds tentative minimum tax, which is when recovery typically begins. Do not forget to file Form 8801: the credit is lost in practice if you never claim it.

    6. 6

      Check your state's AMT and plan multi-year for 2030

      A few states (notably California) have their own AMT and may tax you at the state level even when the federal AMT is modest -- model federal regular, federal AMT, and state AMT together if you live in one. Also plan ahead for 2030, when the SALT cap is scheduled to revert to $10,000: the SALT add-back, historically the biggest AMT driver, partially returns to relevance for itemizers, which can change your AMT exposure independent of anything you do. Build a multi-year view rather than optimizing one year in isolation.

    State variance

    California

    California has its own AMT (currently a 7% rate with a state exemption and phase-out) that operates independently of the federal AMT. A taxpayer can owe California AMT even in a year their federal AMT is small, particularly on ISO exercises -- California conforms to the federal ISO bargain-element adjustment. High-income Californians exercising options should model federal regular tax, federal AMT, and California AMT as three separate layers.

    New York

    New York does not impose a broad standalone individual AMT comparable to California's, so for most New York filers the AMT is a federal-only concern. New York's high ordinary rates still matter for the overall stack, but they do not add a separate state AMT layer on an ISO exercise the way California's regime does.

    Texas

    Texas has no state income tax, so there is no state AMT -- the AMT is purely a federal calculation for Texas residents. The same is true in Florida, Washington, Nevada, Wyoming, South Dakota, Alaska, and Tennessee. Residents of these states modeling an ISO exercise or a large gain only need to run the federal regular-versus-AMT comparison.

    Frequently asked questions

    What happens if I miss the April 15 tax deadline?+
    If you owe tax, the IRS charges two separate penalties: failure to file (5% of unpaid tax per month, max 25% under IRC §6651(a)(1)) and failure to pay (0.5% per month, max 25%). File Form 4868 for an automatic 6-month extension — but the extension only extends the FILING deadline, not the PAYMENT deadline. Interest accrues from April 15 regardless. If you have a clean 3-year history, you may qualify for First Time Abatement (FTA) to waive the failure-to-file penalty.
    Do I need a CPA or can I file my own taxes?+
    Most self-employed people with straightforward Schedule C income can file using tax software (TurboTax, FreeTaxUSA, TaxAct). Consider a CPA or Enrolled Agent (EA) if you have: an S-Corp election, multi-state filing, rental property with cost segregation, your first year of self-employment (to set up correctly), or an IRS notice. EAs are federally licensed and often less expensive than CPAs. The IRS Volunteer Income Tax Assistance (VITA) program offers free help for incomes under $67,000.
    How do quarterly estimated tax payments work?+
    Self-employed people must pay estimated tax quarterly (April 15, June 15, September 15, January 15) if they expect to owe $1,000 or more. The safe harbor under IRC §6654 is paying at least 100% of prior-year tax (110% if AGI exceeded $150,000). Use Form 1040-ES or pay via IRS Direct Pay or EFTPS. Missing payments triggers an underpayment penalty calculated per quarter — even if you pay everything at filing time.
    I thought almost nobody pays AMT anymore. Why should I care in 2026?+
    That was true from 2018 through 2025: the TCJA raised the exemption and phase-out thresholds so high, and the SALT cap removed the biggest trigger, that AMT became rare. OBBBA changes it for 2026. It kept the high exemption but reset the phase-out to start at $500,000 (single) / $1,000,000 (MFJ) and doubled the phase-out rate from 25% to 50%, so the exemption now disappears twice as fast for high earners. Anyone exercising ISOs, holding private-activity municipal bonds, taking large accelerated depreciation, or with income near or above those thresholds should run an AMT projection rather than assume the post-2017 reality still applies.
    Does a big capital gain trigger the AMT?+
    Not directly. Long-term capital gains and qualified dividends keep their preferential 0/15/20% rate inside the AMT -- they are not taxed at 26% or 28%. But a large gain raises your AMTI, and AMTI is what phases out your exemption. So a big one-time gain can push you into the $500,000 / $1,000,000 phase-out band, strip away your AMT exemption, and thereby expose your other (ordinary) income to AMT rates. The gain itself is not AMT-taxed, but it can cause AMT on everything else. That is why a year with a large sale deserves an AMT projection even though the gain is 'just' long-term.
    If I pay AMT, do I ever get it back?+
    Sometimes. AMT from 'timing' items -- the ISO bargain element, accelerated-depreciation differences -- generates a minimum tax credit under Section 53, carried forward indefinitely on Form 8801. In later years where your regular tax exceeds your tentative minimum tax, you recover it. AMT from 'exclusion' items -- private-activity bond interest, the standard deduction add-back, the SALT add-back -- is permanent and generates no credit. So whether your AMT comes back depends entirely on which kind of item caused it. ISO-driven AMT is often recoverable; muni-bond-driven AMT is gone for good.
    How is the AMT guide different from the ISO guide?+
    The ISO Tax Guide covers the AMT specifically as it applies to incentive stock options -- the bargain element, qualifying versus disqualifying dispositions, 83(b) elections, and recovering the AMT credit after a sale. This guide covers the AMT generally: how the parallel tax works for everyone, the 2026 OBBBA phase-out change, the non-ISO triggers (private-activity bonds, depreciation, large gains), the QSBS interaction, and the planning levers. If your AMT question is about stock options, start with the ISO guide; if it is about whether and why you owe AMT at all, start here.

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