The deadline is in the statute itself. Section 83(b)(2) says the election “shall be made not later than 30 days after the date of such transfer.” It also says the election may not be revoked except with IRS consent. Neither sentence leaves room for a grace period.

What follows is how to count those 30 days, which date starts the clock, and what the options look like after a miss. This is general information, not legal or tax advice. Rules and IRS procedures were checked against IRS and eCFR pages on November 5, 2026.

The rule, from the IRS form

The instructions to IRS Form 15620 restate it in plain terms:

1. The election must be filed no later than 30 days after the date the property was transferred.
2. Under section 7503, if the 30th day falls on a Saturday, Sunday or legal holiday, the election is timely if it is postmarked by the next day that is not a Saturday, Sunday or legal holiday.

The regulation at 26 CFR 1.83-2(b) adds one more point founders rarely hear: the election “may be filed prior to the date of transfer.”

Counting: the transfer date is day zero

Count the day after the transfer as day 1. Day 30 is the last day, subject to the weekend and holiday rule.

The weekend and holiday rule is a safety net, not a plan. The safer reading is to treat day 30 as the deadline whatever day it lands on, and to file in the first week.

Three counting mistakes

• Counting from the board consent. The board approving an issuance is not the transfer. The clock runs from the transfer itself, but a consent dated earlier is a reason to file early, not late.
• Counting business days. The statute says 30 days. Weekends and holidays inside the window count.
• Counting from when the paperwork arrived. A founder who receives a signed purchase agreement by email two weeks after it was dated has 16 days left, not 30.

Which date is the transfer date

Form 15620 asks for “the date the property is transferred” in Box 3, and points to 26 CFR 1.83-3(a) for what counts as a transfer. For founder stock, that is ordinarily the date the founder acquires the shares under the restricted stock purchase agreement.

Problems arise when documents disagree. The board consent approving the issuance is dated one day, the purchase agreement another, and payment arrives a week later. When dates differ, the founder’s counsel should decide which date controls, and the founder should file within 30 days of the earliest plausible date. Filing early costs nothing, since the regulation allows filing before transfer.

Online or mail

As of November 5, 2026, the IRS mobile-friendly forms page lists Form 15620, with an IRS Online Account required. After completing the form, the filer can submit it online or download a copy for mailing.

Two practical points on online filing. First, identity verification for a new IRS account can take time, so a founder who plans to file online should set up the account before the stock is issued. Second, file once. Submitting online and also mailing a paper copy creates two records of the same election.

For mail, certified mail with a return receipt gives a dated postmark and proof of delivery. Keep the receipt with a copy of the signed form.

Day-by-day plan

Assumptions
- Stock purchase agreement signed and shares issued on day 0
- Founder will file online; IRS account already set up

Day -7   Create or confirm IRS Online Account; collect SSN, address,
         share count, price per share, fair market value per share
Day 0    Sign purchase agreement; pay for shares; note transfer date
Day 1-3  Complete Form 15620 (Box 8 income is $0 if price = value)
Day 3    Submit online; download the confirmation
Day 3    Send a copy to the company; company files it with the
         stock records
Day 7    Second founder confirms the same steps are done
Day 30   Last day (subject to the weekend and holiday rule)

After a missed deadline

There is no general late-filing relief for this election. The 30 days come from the statute, and a late election does not satisfy it. What remains is a choice among imperfect options, each of which needs a tax adviser.

Live with the default rule. The founder recognizes ordinary income as shares vest, at each vesting date’s value. If the company’s value stays low, the cost may be small. If the company raises money at a higher price, it can be large. Plan for it rather than discovering it at tax time.

Unwind and reissue. The company and founder may cancel or repurchase the original shares and issue new restricted stock, starting a new 30-day clock. The new purchase price has to reflect current fair market value, and the unwind itself can have tax consequences. This works best soon after the miss, before the company’s value moves.

Change the vesting. If the shares are made fully vested now, there is nothing left to elect; the founder is taxed on the current spread. The company then gives up the protection vesting provides, which future investors may ask to restore.

For context on why the election matters at all, see 83(b) election explained, which runs the same founder’s numbers with and without it.

Revocation is not a fix for timing

The form instructions say an election cannot be revoked without IRS consent, and point to 26 CFR 1.83-2(f) and Revenue Procedure 2006-31 for the rules. Revocation addresses an election that should not have been made. It does nothing for one that was never filed on time.

Questions about the deadline

Does the 30-day clock pause for weekends? No. Weekends and holidays count. Only day 30 itself can shift, and only to the next business day.

Does filing a tax return later fix it? No. The election is a separate filing due within 30 days. The regulation no longer requires a copy to be attached to the return.

Who keeps the copy? The founder and the company. The regulation requires the founder to give a copy to the company. Investors’ counsel will ask for it during diligence, as the how to start a startup company checklist notes.

Does the deadline apply to each founder separately? Yes. Each founder files a separate election for their own shares, within 30 days of their own transfer date.

Is the deadline the same for stock received from an early option exercise? Yes. The clock runs from the date the exercised shares are transferred.