§83(b) Election: The 30-Day Rule That Founders Blow

What §83(b) Does (And Why It Matters)

• When you receive restricted stock — founder shares with reverse vesting, restricted stock awards (RSAs), or any property subject to a substantial risk of forfeiture — §83 says you're taxed *at vesting* on the FMV at that time, not at grant.
• For a founder, that's catastrophic: if you got founder stock at $0.0001/share and the company hits a $20M valuation 2 years later, your 'income' on each vesting tranche is the spread — at ordinary income tax rates, potentially 35-45%.
• The §83(b) election flips the timing: you elect to recognize the income *now* (at grant, when value ≈ what you paid), then any subsequent appreciation is taxed at *long-term capital gains* when you eventually sell — a 15-20 point tax-rate spread on millions of dollars of upside.
• Concrete: founder stock granted at $1,000 total cost. No §83(b): you owe ordinary tax on the spread each vesting cliff for 4 years. WITH §83(b): you pay tax on $0 today (since FMV ≈ purchase price), and the entire future gain is capital.