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ISO AMT Planning Guide

The #1 pain point in equity compensation planning: AMT exposure from ISO exercises (often without liquidity).

Last updated: January 2026

The #1 pain point in equity compensation planning

For many equity comp clients, the hardest part of the plan isn’t the math — it’s the mismatch between taxable income and cash. ISOs can create a large tax bill in a year where the client never sold shares and didn’t generate liquidity.

What is the Alternative Minimum Tax (AMT)?

The AMT is a parallel tax system that runs alongside the regular federal income tax. Each year, a taxpayer calculates liability under both systems and pays whichever is higher.

For equity compensation, AMT matters because ISO exercises (when the client exercises and holds) create an AMT “preference item” — the spread is included in AMT income even though there’s no sale.

2026 AMT parameters (OBBBA changes)

Parameter20252026 (OBBBA)
Exemption (Single)$88,100$90,100
Exemption (MFJ)$137,000$140,200
Phase-out begins (Single)$626,350$500,000
Phase-out begins (MFJ)$1,252,700$1,000,000
Phase-out rate25%50%
AMT rates26% / 28%26% / 28%
Key change for 2026
The accelerated phase-out (50% vs. 25%) means AMT exemptions disappear faster. In practice, more clients will be affected — and the “safe” ISO exercise window can shrink materially.

How ISOs trigger AMT

When a client exercises ISOs and holds the shares, the “bargain element” (FMV − strike) is not taxed under regular income tax — but it is included in AMT income.

Example: ISO exercise AMT calculation

ElementValue
Options exercised10,000 shares
Strike price$5/share
FMV at exercise$25/share
Bargain element$200,000 (10,000 × $20)
Cash outlay to exercise$50,000
AMT preference item$200,000
Potential AMT (upper-bound heuristic)Up to $56,000 (28% of $200,000)
The AMT trap
In the example above, the client could have a $50,000 cash outlay to exercise and a large AMT liability — with no stock sale to generate cash.
AMT calculation note
The “spread × 28%” number is a rough upper-bound heuristic. Actual AMT depends on the exemption, phase-out, and the gap between regular tax and tentative minimum tax. Always model precise scenarios.

Six strategies to minimize ISO AMT

  1. Find the AMT crossover point. Model the maximum ISO spread the client can exercise without triggering AMT, then exercise up to that threshold annually.
  2. Exercise early in the year. January/February exercises preserve flexibility — if shares drop significantly, a same-year disqualifying disposition may reduce total tax vs. paying AMT on a higher spread.
  3. Spread exercises across years. Break a large exercise into 2–4 years to stay below AMT thresholds each year (especially important with 2026’s accelerated phase-out).
  4. Coordinate with high-income years. In a year with large bonuses/RSUs/cap gains, AMT may not exceed regular tax — the marginal benefit of ISO treatment can change.
  5. Plan around AMT credits. AMT paid on ISO exercises can generate an AMT credit that may offset future regular tax — but recovery can take years.
  6. Same-day sale (DD) when needed. Exercise-and-sell avoids AMT entirely. The spread is ordinary income, but cash is immediate and holding risk is removed.
Advisor tip
Model AMT across 3–5 years, not just the current year. Single-year projections often miss planning options that only show up in a multi-year view.