83(b) Election: Complete Decision Guide for Stock Options

The 83(b) election can convert six figures of ordinary income into long-term capital gain — or cost you money if your company doesn't succeed. Here's the full framework, including how to file before the 30-day window closes.

What the 83(b) election does

Under IRC § 83, property received in connection with services — including restricted shares from an early-exercised option grant — is taxed as ordinary income when it vests. The taxable amount is the spread between fair market value at vesting and whatever you paid (the strike price). You don't get to choose when this happens; vesting is the event that triggers ordinary income, regardless of whether you sell a single share.¹

The 83(b) election shifts that event. By filing an election under IRC § 83(b) within 30 days of the exercise date, you agree to be taxed on the spread as it exists at exercise rather than at vesting. If you exercise shortly after grant when the 409A fair market value is close to the strike price, the taxable spread is near zero. All appreciation from that point forward is then taxed as capital gain — long-term capital gain (20% federal rate) if you hold the shares for more than 12 months after exercise.²

That's the core trade: pay ordinary income tax on a small spread today, convert future appreciation to lower-rate capital gain.

The tax math in a concrete scenario

Suppose you have options to purchase 100,000 shares at a strike of $0.10/share. The current 409A FMV is $0.40/share. You expect the company to reach $20/share at vesting in four years.

Federal taxes only. State taxes vary significantly (CA taxes ISO spreads as ordinary income and follows federal AMT mechanics; other states vary). Use the 83(b) calculator for your specific numbers.

The savings are large because the 83(b) election converts nearly all the gain from ordinary income rates (37% + NIIT = 40.8% in top bracket) to long-term capital gain rates (20% + 3.8% NIIT). The break-even is approximately: "will this company appreciate meaningfully from current 409A?" If yes, the election is almost always worth filing when the cost to exercise is affordable.

How the election applies to ISOs, NQSOs, and restricted stock

The 83(b) election only applies to unvested property — you must have exercised options before they are fully vested (an "early exercise"), or received restricted stock that vests over time. Exercising fully-vested options has no 83(b) component because there's no future vesting event to shift.

One nuance for ISOs: shares received via early exercise with an 83(b) election are no longer treated as options — they're treated as direct stock purchases for tax purposes. The ISO holding period (2 years from grant, 1 year from exercise) still applies for qualifying-disposition treatment, but the AMT preference item is the spread at the early-exercise date rather than at the later vesting date.¹

The QSBS connection

If your employer is a C-corporation that qualified as a Qualified Small Business (QSB) under IRC § 1202 at the time of issuance — meaning it had under $75 million in gross assets at the time your shares were issued (the $75M ceiling was raised from $50M by OBBBA in July 2025) — your shares may qualify for the § 1202 exclusion.³

Under OBBBA's tiered structure, the gain exclusion depends on how long you hold the shares:

• 3 years held → 50% gain excluded (up to $15M of gain per issuer)
• 4 years held → 75% excluded
• 5 years held → 100% excluded (the original rule; now also the cap under OBBBA)

This is where the 83(b) election becomes doubly valuable for pre-seed and seed-stage employees: the QSBS five-year clock runs from the acquisition date of the shares. If you file an 83(b) election and acquire shares today, the clock starts today. If you wait for vesting, the QSBS clock doesn't start until each tranche vests — potentially delaying 100% exclusion by the full vesting schedule.

For a $2M gain at a $0.40/share early exercise with QSBS eligibility, filing the 83(b) and holding 5 years could mean $0 federal tax on that gain. Waiting for standard vesting and starting the QSBS clock 4 years later means you'd need to hold 5 more years (9 years total) for full exclusion. The math strongly favors early exercise + 83(b) for eligible companies when you believe in the upside.

Important QSBS limitations: the company must be a domestic C-corp; stock must be acquired at original issuance for money or services (not on secondary market); your shares must have been issued when aggregate gross assets were under $75M; and you must hold throughout the required period without transferring to a non-eligible holder. CA and a handful of other states do not conform to the federal QSBS exclusion — state tax applies in full.

When to file — and when to skip

How to file

Since November 2024, the IRS offers a standardized form: Form 15620, Section 83(b) Election (Rev. 4-2025). You can use Form 15620 or a written statement — both are acceptable under Treas. Reg. § 1.83-2(e).⁴

1. Complete the election document. Use Form 15620 or a written statement. Required information: your name, address, TIN; a description of the property (number of shares, company, grant date); the date of transfer and the tax year; the nature of any restrictions on the shares; the fair market value at the time of transfer; any amount paid for the property; and a statement that copies have been provided to required persons.
2. File with the IRS within 30 days of the exercise date. Mail to the IRS Service Center where you file your federal income tax return. Use certified mail with return receipt requested — you need proof of timely filing. No electronic filing option exists; mail is required. The 30-day clock runs from the exercise date, not from the date you receive the stock certificates.
3. Provide a copy to your employer. IRC § 83(b) requires you to give a copy to the company (or its stock plan administrator). Most companies require this as part of their early-exercise documentation process.
4. Keep your records. Retain the election document, the certified mail receipt and return receipt green card, and any employer acknowledgment. You will need to demonstrate timely filing if the IRS questions your capital gain treatment years later.
5. File your taxes as normal. As of 2016, you no longer need to attach a copy of the 83(b) election to your income tax return — the prior regulation requiring this was repealed (T.D. 9779, effective July 26, 2016).⁵ However, you should still report the ordinary income (if any) recognized at exercise on your return for the year of exercise.

Common mistakes

What a specialist models that you can't from a calculator alone

A fee-only advisor who specializes in equity compensation will model dimensions of the 83(b) decision that require integrating your entire financial picture:

• State tax exposure. California taxes the spread on early-exercised ISOs as ordinary income under California conformity rules — regardless of the federal AMT treatment. The 83(b) election in California shifts that ordinary income to exercise date, but the state tax math differs materially from federal. NY, MA, and other high-tax states have similar complexity.
• Multi-year AMT planning. If you're exercising ISOs, the 83(b) election sets your AMT basis but the AMT credit carryforward interacts with future exercises, disqualifying dispositions, and ordinary income levels in ways that require modeling across several tax years.
• Cash-flow sequencing. Exercising early costs cash today (strike × shares + any tax on spread). An advisor can model the opportunity cost of tying up that capital vs. keeping the option open — including scenarios where the company fails.
• QSBS verification and stacking. An advisor can verify QSBS eligibility, model the gross-asset ceiling for multiple issuances (if you have multiple grant tranches), and structure the 83(b) + QSBS play correctly when the company is close to the $75M gross-asset threshold.
• Timing relative to valuation cycles. 409A valuations are updated roughly every 12 months or after a funding round. The optimal window to early-exercise is often right after grant, before the next 409A step-up. An advisor tracking your grant schedule can flag this window before it closes.

The 83(b) decision involves a 30-day deadline, irreversible consequences, and an interaction between federal, state, AMT, QSBS, and ISO rules that changes based on your income, your company's trajectory, and your personal risk tolerance. A specialist who has modeled hundreds of these has pattern-matched on situations you haven't encountered before.