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Equity Compensation

Early Exercise vs. Waiting: A Hypothetical Tax Illustration

A hypothetical walk-through of ISO tax mechanics: exercising at grant can avoid AMT that a later exercise may trigger, at the cost of risking cash early.

Early Exercise vs. Waiting: A Hypothetical Tax Illustration

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What does this illustration show?

  • This is a hypothetical example of federal tax mechanics, not a client result and not a prediction of any company's value.
  • It compares exercising ISOs at grant, when the strike equals the 409A value, with exercising after the 409A has risen.
  • It assumes no investment returns and uses 2026 federal rules; state tax, including California's, is left out.
  • Real outcomes depend on your income, grant terms, and tax law in the year you act.
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Early Exercise and the 83(b) Election, ExplainedHow Employee Stock Options Work: A Plain-English PrimerAlternative Minimum Tax (AMT) Planning

Full Guide

What does this illustration show?

  • This is a hypothetical example of federal tax mechanics, not a client result and not a prediction of any company's value.
  • It compares exercising ISOs at grant, when the strike equals the 409A value, with exercising after the 409A has risen.
  • It assumes no investment returns and uses 2026 federal rules; state tax, including California's, is left out.
  • Real outcomes depend on your income, grant terms, and tax law in the year you act.

What are the assumptions?

  • Single filer with a $250,000 salary, the standard deduction, and no other income in the year of exercise.
  • Grant of 50,000 ISOs at a $0.50 strike, with a $0.50 409A value at grant and four-year vesting.
  • The plan permits early exercise of unvested options, and an 83(b) election is filed within 30 days.
  • Path A exercises everything at grant; Path B exercises everything in a later year when the 409A is $10.00.

Path A: what happens when you exercise at grant?

  • Cash out of pocket is $25,000 (50,000 × $0.50).
  • The spread is zero, so there is no regular income and no AMT adjustment.
  • For unvested ISO shares, the 83(b) election matters for AMT; IRS Form 15620 can be used to make it.
  • If you leave before vesting, the company can usually repurchase unvested shares, often at your original cost.

Path B: what happens when you exercise after the 409A rises?

  • Cash for the exercise is still $25,000, but the spread is $475,000 (50,000 × $9.50), an AMT adjustment.
  • Using 2026 figures, regular tax on the salary is about $51,300, and the AMT exemption fully phases out at this income.
  • Tentative minimum tax is about $198,100, so roughly $146,800 of AMT is due on top of the exercise cost.
  • Some AMT may be recovered later as a minimum tax credit, but the timing is uncertain and can take years.

What is the same in both paths, and what differs?

  • In a qualifying disposition, regular-tax basis is $0.50 either way, so the federal long-term gain on sale is the same.
  • The key difference is the AMT cash needed in Path B and how long it takes to recover as a credit.
  • Path A also starts the ISO holding periods earlier, so shares can reach qualifying-disposition status sooner.
  • If the company qualifies for QSBS, stock issued after July 4, 2025 can earn a 50%, 75%, or 100% exclusion at three, four, or five years; California does not conform.

What could go wrong with exercising early?

  • Many startups fail; the $25,000 could be lost entirely, with only a limited capital-loss deduction.
  • The cash is tied up for years in shares you usually cannot sell.
  • If the 409A already exceeds the strike when you exercise early, the spread can create AMT or, for NSOs, ordinary income.
  • Missing the 30-day 83(b) deadline can create tax as each tranche vests, undoing much of the benefit.

Key takeaways

  • Early exercise mainly trades early cash at risk for less AMT exposure and earlier holding-period clocks.
  • The benefit is largest when the strike equals the 409A value and the company later grows in value.
  • It can make sense only with money you could afford to lose entirely.
  • Confirm the math with a CPA before acting; Rubric does not prepare tax returns or give legal advice.
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Early Exercise and the 83(b) Election, Explained

Early exercise lets you buy unvested option shares now. An 83(b) election, due within 30 days, taxes them at today's value instead of at each vest.

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How Employee Stock Options Work: A Plain-English Primer

A stock option is the right to buy company shares at a fixed strike price. ISOs and NSOs are taxed differently, and ISOs can trigger AMT at exercise.

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Alternative Minimum Tax (AMT) Planning

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