The 83(b) election deadline is 30 days from the date your restricted stock is granted, and the IRS does not care about your excuse. No extensions, no late filing relief, no exceptions for founders who were too busy raising a seed round to read the fine print. Miss the window and you lock in the worst possible tax outcome: paying ordinary income tax on stock as it vests, at whatever its value happens to be later, instead of at the pennies-per-share price it was worth on day one.
When you receive restricted stock, whether as a founder or an early employee, the IRS does not tax you at grant. It taxes you when the stock vests, because vesting is the moment you actually own it without risk of forfeiture. The problem is that most startup stock vests over four years, and if the company does well, the value at each vesting date keeps climbing. You end up paying ordinary income tax, at your regular rate, on a rising share price you never got to choose.
An 83(b) election changes the trigger date. You tell the IRS, in writing, that you want to be taxed now, at grant, on the full value of the stock, even though it has not vested yet. If the stock is worth almost nothing at grant, which is typical for a founder's shares right after incorporation, your tax bill is close to zero. Everything the stock earns after that point becomes a capital gain, taxed at a lower rate, and only realized when you actually sell.
This is not a loophole. It is a timing election Congress built into the tax code on purpose, specifically for situations where an asset's value is expected to grow substantially after grant. Founders are the textbook use case.
The clock starts on the date of grant, not the date you sign your stock purchase agreement, not the date your lawyer gets around to it, not the date the board approves the cap table update. Thirty calendar days, including weekends. If day 30 lands on a Sunday, you do not get until Monday. File it before the deadline, not on it, because mail delays and processing errors happen.
The filing itself is simple: a short letter to the IRS describing the property, the date of transfer, the fair market value, and the amount paid. You mail it to the IRS service center where you file your return, keep a copy, and attach another copy to your tax return for that year. As of 2025 there is no online portal for this. It is paper, certified mail, return receipt requested, because you need proof of the postmark if the IRS ever questions the timing.
There used to be a requirement to send a copy to the company too. The IRS dropped that formal filing requirement for the company's tax return, but keep the founder-side paperwork clean regardless. Lawyers still recommend sending a copy to the company for the cap table file.
Founders issuing themselves restricted stock at incorporation are the clearest case. Early employees who receive restricted stock, not options, before a priced round also need it. This gets confused constantly: 83(b) elections apply to restricted stock, not to standard incentive stock options or non-qualified options, unless those options are early-exercised into restricted shares before vesting.
If you early-exercise options, meaning you pay for the shares before they vest and hold unvested stock subject to a repurchase right, you have the same exposure as a restricted stock grant, and the same 30-day clock applies from the date of exercise. This is a common structure at early-stage companies specifically because it lets employees file the election while the strike price and the fair market value are still nearly identical, producing close to zero tax due.
Anyone joining a company after a real valuation exists, where the stock is worth meaningfully more than the strike price, faces a much bigger decision. Filing still starts the capital gains clock, but it also means writing a real check to the IRS for stock you cannot yet sell. That tradeoff needs actual math, not a reflexive yes.
Say a founder is granted 4 million shares at incorporation, worth $0.0001 each. Total value: $400. File the 83(b) election, pay tax on $400 of ordinary income, essentially nothing. Four years later the company is worth $200 million and those shares are worth $50 million. Sell them, and the gain is taxed at long-term capital gains rates, assuming a holding period over one year from the election date.
Without the election, that same founder gets taxed at ordinary income rates on the fair market value of each vesting tranche, as it vests. If the company's valuation climbs steadily, each quarterly vesting event triggers tax on stock worth more than the last. Instead of one near-zero tax event and a capital gains position, the founder owes ordinary income tax repeatedly, on an asset they cannot sell to cover the bill, because private company stock has no liquid market.
That last point is the real danger. Restricted stock in a private company is illiquid. You cannot sell a slice to pay the IRS. Without the election, you can owe real tax money on paper wealth you cannot touch, year after year, until the company either goes public or gets acquired.
You lose the election permanently. There is no do-over, no appeal, no reasonable-cause exception the way there sometimes is for other IRS filings. The default tax treatment applies automatically, and it is the worse one in almost every startup scenario where the company is expected to grow.
Some founders discover this the hard way during a tax return review, months after the grant, when an accountant asks "did you file an 83(b)?" and the answer is no. At that point there is nothing to fix. The only real remedy is prevention: file the moment the grant happens, not after the lawyers finish the paperwork, not after the first board meeting, not after you feel settled into the company.
Some early-stage companies now build the election into the onboarding paperwork specifically to avoid this failure mode, handing new hires a pre-filled letter and a stamped envelope on day one. That is a low bar to clear, and any company issuing restricted stock without that process is doing its people a disservice.
Do not rely on your company to file this for you. It is your personal election, your responsibility, and your tax exposure if it goes wrong. Use certified mail with a return receipt. Keep the green card that comes back as proof of delivery.
Include a personal check for any tax due, even if it is small. Attach a copy of the filed election to your federal tax return for the year of the grant, on Schedule 1 or as an attachment depending on your software. Keep a full copy of everything, mailing envelope included, in a folder you will not lose, because you may need to produce it years later when you sell.
If you are a first-time founder issuing your own shares, get a lawyer or a tax advisor who has actually filed dozens of these to check your letter before it goes out. The form of the letter matters less than the timing. A slightly imperfect letter filed on day 15 beats a perfect one filed on day 31.
You have 30 calendar days from the date your restricted stock is granted, or from the date you early-exercise unvested options, to mail the election to the IRS. Weekends and holidays count toward the 30 days, and there is no extension available under any circumstance. Missing it by even one day forfeits the election permanently.
No. Unlike many other IRS deadlines, the 83(b) election has no reasonable-cause exception, no late-filing relief, and no appeals process. The IRS treats this as a strict statutory deadline, and once it passes the default tax treatment applies with no way to reverse it.
It applies to restricted stock, not standard vested options. However, if you early-exercise unvested stock options and hold shares subject to a company repurchase right, that unvested stock is treated like restricted stock, and the same 30-day election window starts from your exercise date.
You do not get the tax you already paid back. If you filed the election and paid tax on the stock's value at grant, and the company later fails or the stock becomes worthless, you generally cannot recover that tax through a refund, though you may be able to claim a capital loss depending on your situation. This is the core risk of filing for anyone joining after a real valuation already exists.
The IRS no longer requires the company to attach a copy to its own return, but it is still standard practice to give your employer or your own company a copy for the cap table and legal file. You must keep your own copy and attach one to your personal tax return for the year of the grant.