Filing an 83(b) election: what it is, who does it, and why

An 83(b) election is a one-page letter you mail to the IRS that can save you tens or hundreds of thousands of dollars in tax. It is also the single most common tax-paperwork mistake first-time founders make, because there is a hard 30-day deadline and missing it is irreversible. If you have just been granted equity that vests over time, this is the post you want to read today, not next month.

What it actually is

Section 83 of the Internal Revenue Code says that when you receive property (like company stock) in connection with services, you owe ordinary income tax on the value of that property as it vests. Not when you sell it. As it vests. So if you got 1,000,000 shares of founder stock worth $0.0001 each, and over four years those shares vest while the company gets more valuable, you would technically owe income tax on each tranche of vested shares at whatever the company is worth on the day they vest.

Section 83(b) is the escape hatch. It lets you tell the IRS, "I would rather pay the tax now, on today's value, on the entire grant, including the unvested portion." The election essentially treats the whole grant as if it had vested on day one for tax purposes. The legal vesting schedule does not change; only the tax timing does.

Why you do it

The election is almost always a good idea when the value of the equity at the moment of grant is very low and you expect it to go up. A quick example. You found a Delaware C-Corp, issue yourself 8,000,000 shares at $0.00001 par, and sign a four-year vesting schedule. The total fair-market value of the grant is $80. If you file an 83(b), you pay ordinary income tax on $80 today (so, basically nothing) and the holding-period clock starts immediately for capital-gains purposes.

Now skip forward two years. The company raises a Series A at a valuation that makes your stock worth $5,000,000. Without an 83(b), you would have been recognizing ordinary income every quarter as your shares vested at the new, higher value. Some founders end up with hundreds of thousands of dollars of phantom income on stock they cannot sell. With an 83(b), the only tax event was the $80 you reported on day one. Everything that happens afterward is treated as a capital gain when you eventually sell.

The election also matters for the long-term capital gains rate. Long-term gains require a one-year holding period, and the 83(b) starts that clock at grant rather than at vest. For founders sitting on a C-Corp who later qualify for the QSBS exclusion (Section 1202), the five-year holding period also runs from the 83(b) date.

Who actually files one

The 83(b) is relevant any time you receive equity that vests, where the tax code would otherwise tax you as it vests. The most common situations:

1. Founders of a Delaware C-Corp who issue themselves restricted stock subject to a vesting schedule. This is the textbook case and the one almost every YC-style startup deals with on day one.
2. Early employees who receive restricted stock awards (RSAs) instead of options. Less common at later-stage startups, but it shows up at very early-stage companies.
3. LLC members who receive a profits interest with vesting, in some structures. Whether you need to file depends on whether the profits interest is "safe-harbor" under Rev. Proc. 93-27. Talk to a tax accountant; do not freelance this one.
4. Anyone exercising stock options early (an "early exercise") on shares that are still subject to vesting. Early exercise without an 83(b) is almost always a bad deal.

You do not file an 83(b) for vested stock you bought outright (no vesting means nothing to elect against), for ordinary stock options you have not yet exercised, or for RSUs (those are governed by a different code section entirely). If you are still deciding whether to form an LLC or a C-Corp in the first place, our walkthrough of LLC vs C-Corp covers when each makes sense and why most founders only run into the 83(b) question after they have picked a corporation.

The 30-day deadline

Here is the trap. The 83(b) must be postmarked and mailed to the IRS within 30 days of the date you receive the stock, not 30 days from when you signed the paperwork or when the lawyer got back to you. Day 1 is the day after the transfer. Day 30 is hard. If you miss it, you cannot file late, you cannot extend, and you cannot fix it. The IRS does not accept "I forgot" as a reason. We have seen founders lose six and seven figures of avoidable tax to a missed 30-day window.

The clock also runs over weekends and holidays. If day 30 falls on a Sunday, you mail it on the Friday before. Mail it certified, with return receipt requested, and keep the green card in your records forever. You will want it years later if the IRS ever asks for proof.

How to actually file

The mechanics are simple, which is part of why missing the deadline stings so much. Here is the practical workflow most founders use:

1. Sign the stock purchase agreement and pay for the shares (even if it is a few dollars). Note the exact transfer date.
2. Fill out the 83(b) election letter. There is no official IRS form; the instructions in the regs specify what the letter has to contain (your name, address, taxpayer ID, a description of the property, the date of transfer, the nature of the restriction, the fair market value, and the amount paid).
3. Sign two copies. Mail the original to the IRS office where you file your personal return. Send the second copy to your company so it goes in the cap-table file.
4. Use certified mail with return receipt. Keep the green card and the certified-mail receipt with your tax records.
5. Attach a copy to your personal tax return for that year. (As of 2020 the IRS no longer requires the copy to be attached, but most tax preparers still do it for safety.)

The IRS has been on a slow march to allow electronic 83(b) filings; some flows now accept them via the secure-message portal. Read the current IRS guidance before filing because the rules have moved a few times in the last several years. When in doubt, mail it. Paper with a postmark is a paper trail no one can take away from you.

Common mistakes

• Missing the 30-day window because the stock purchase agreement was signed before everyone got around to filing. The clock starts at transfer, not at signing of the 83(b).
• Filing an 83(b) on stock that does not actually have a vesting schedule. There is nothing to elect against, and you are creating a paper record for no reason.
• Forgetting to send a copy to the company. Cap-table software (Carta, Pulley, AngelList) will ask for it.
• Ignoring the state tax side. A few states have their own analog to the 83(b) and a few do not recognize the federal election cleanly. California, in particular, has its own rules. Talk to a state-savvy CPA if your state matters.
• Filing one for RSUs. RSUs are governed by Section 451, not 83. The 83(b) does not apply and filing one anyway just confuses the IRS.

Frequently asked questions

What if my company stays small forever? Then the 83(b) was a tiny tax bill on day one and you got nothing dramatic out of it. The downside of filing is small. The downside of not filing is large. The expected value is overwhelmingly in favor of filing.

What if the company fails? The income you reported on the 83(b) is not refundable. That is the only real risk, and it is why people sometimes hesitate when the grant has a meaningful value. For most founders with sub-dollar founder stock, the risk is rounding error.

Do LLC members ever file an 83(b)? Sometimes. If you are receiving a profits interest that does not fit cleanly inside the Rev. Proc. 93-27 safe harbor, an 83(b) is often filed defensively. This is one of the few areas where it is genuinely worth paying an accountant before you do anything. The election itself is also conceptually related to the IRS election logic in our post on what an S-Corp actually is. Both are cases where you are choosing how the IRS treats something rather than changing the legal structure of the company.

Can my lawyer or accountant file it for me? They can prepare and mail it, but the signature and the responsibility are yours. You are the one who eats the consequences if the deadline is missed, so check the date personally.

Read next: If the 83(b) question came up because you are deciding between an LLC and a Delaware C-Corp, the entity choice is the bigger decision. Start with LLC vs C-Corp. If you are an LLC owner curious about other tax elections, see What is an S-Corp. And the federal tax ID you will need either way is the EIN. Ready to file? Form your LLC with EntityEngine.