# The $100,000 ISO limit and early exercise

> The $100,000 a year that can first become exercisable as ISOs, and why early exercise runs into it.

Source: https://lopifi.com/learn/employee-stock-options-iso-vs-nso/iso-100000-limit-and-early-exercise
Part of: Lopifi — US GAAP books on autopilot, checked by a CPA (https://lopifi.com)

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**What is the $100,000 ISO limit, and how does early exercise affect it?** The $100,000 a year that can first become exercisable as ISOs, and why early exercise runs into it.

Only $100,000 of stock, valued at the grant-date fair market value, may first become exercisable as [ISOs](https://lopifi.com/md/glossary/incentive-stock-option) in any calendar year; the rest are [NSOs](https://lopifi.com/md/glossary/nonstatutory-stock-option). On ordinary vesting the limit rarely bites, because a grant becomes exercisable a slice a year. [Early exercise](https://lopifi.com/md/glossary/early-exercise) makes the whole grant exercisable at once.

> “exceeds $100,000, such options shall be treated as options which are not incentive stock options”

— [26 U.S.C. §422(d)(1)](https://www.law.cornell.edu/uscode/text/26/422), The $100,000 limit on ISOs first exercisable in a calendar year

**Scenario — A VP's grant, two ways.** After the Seed, Northwind hires a VP with 500,000 options at a $0.25 409A value: $125,000 of stock. On four-year vesting, the most that first becomes exercisable in a year is 135,416 options in 2028 — $33,854, all ISO. Early-exercisable from the grant, all 500,000 are first exercisable in 2027: 400,000 ISOs and 100,000 NSOs.

| Year | Options | Value at grant | ISO | NSO |
| --- | --- | --- | --- | --- |
| 2028 (vesting) | 135,416 | $33,854 | 135,416 | 0 |
| 2029 (vesting) | 125,000 | $31,250 | 125,000 | 0 |
| 2030 (vesting) | 125,000 | $31,250 | 125,000 | 0 |
| 2031 (vesting) | 114,584 | $28,646 | 114,584 | 0 |
| 2027 (early exercise) | 500,000 | $125,000 | 400,000 | 100,000 |

The same grant, by the year its options first become exercisable.

*[Figure: vesting]*

The VP's 500,000 options with early exercise: the 83(b) plate is what makes early exercise worth it — and the whole grant is exercisable from day one.

Early exercise turns options into restricted stock the company can buy back, so the holder can file an 83(b) election within 30 days and start the ISO holding periods at once: ISO stock must be held two years from grant and one year from exercise for the gain to be capital — exercised at grant, that is November 1, 2029 at the earliest.

> “You satisfy the holding period requirement if you don’t sell the stock until the end of the later of the 1-year period after the stock was transferred to you or the 2-year period after the option was granted.”

— [IRS Pub. 525 (2025), Statutory Stock Options — Holding period requirement](https://www.irs.gov/publications/p525), ISO stock: one year from exercise and two from grant

**Exercise — ISO or NSO?.** Only $100,000 of stock, valued at the grant-date fair market value, can first become exercisable as ISOs in one calendar year. Split each row into ISOs and NSOs. Count only the grant on the row. Type it in the workbook at https://lopifi.com/playground.

## Where this page's rules come from

- [26 U.S.C. §422(d)(1)](https://www.law.cornell.edu/uscode/text/26/422) — The $100,000 limit on ISOs first exercisable in a calendar year (statute)
- [IRS Pub. 525 (2025), Statutory Stock Options — Holding period requirement](https://www.irs.gov/publications/p525) — ISO stock: one year from exercise and two from grant (irs)
- [26 U.S.C. §83(b)(2)](https://www.law.cornell.edu/uscode/text/26/83) — Property transferred for services, and the 83(b) election's 30 days (statute)

- **Track:** [Cap tables & raising](https://lopifi.com/md/learn/equity)
- **Part of:** [Employee stock options: ISOs, NSOs and RSUs](https://lopifi.com/md/learn/employee-stock-options-iso-vs-nso) — 6 min
- **Terms taught:** [Incentive stock option](https://lopifi.com/md/glossary/incentive-stock-option), [Nonstatutory stock option](https://lopifi.com/md/glossary/nonstatutory-stock-option), [Early exercise](https://lopifi.com/md/glossary/early-exercise)
- **Previous:** [The 409A valuation and the strike price](https://lopifi.com/md/learn/employee-stock-options-iso-vs-nso/409a-valuation-and-strike-price)
- **Next:** [The 90-day exercise window](https://lopifi.com/md/learn/employee-stock-options-iso-vs-nso/post-termination-exercise-window)
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