The vesting cliff is one of the most consequential — and least understood — aspects of startup equity. Most employees know it exists. Few have thought through how it should affect their career decisions.
How the cliff works
A standard startup grant is '4 years with a 1-year cliff.' You receive 0% of your grant if you leave before month 12. At month 12, you receive 25% at once (the cliff vest). After that, vesting is typically monthly or quarterly — you accrue equity continuously.
The decision calculus before the cliff
Before your cliff, the math is brutal: if you leave, you forfeit the entire grant. If you're considering a job change in months 1–11, your calculation should include: (1) the value of the cliff equity you'd forfeit, and (2) whether your new employer will provide a 'cliff buy-out' — a signing bonus or accelerated new grant to compensate for the lost cliff.
After the cliff: the strategic window
Month 12 is actually the best time to evaluate whether you want to stay. You've received your first 25% tranche. You're no longer subject to the all-or-nothing cliff penalty. And you have more information about the company (its growth trajectory, your fit, the team) than you did when you joined.
How to negotiate the cliff in a new offer
When moving to a new company, you can often negotiate: (1) a shorter cliff (6 months instead of 12), (2) cliff-free vesting (monthly from day 1), or (3) a signing bonus timed to your old company's cliff date. Large tech companies routinely offer these concessions to senior employees — it's worth asking explicitly.
What happens to unvested equity when you leave
Unvested equity generally returns to the company's equity pool when you leave. Your vested equity (post-cliff) remains yours. For RSU holders at private companies, there's a complication: your vested shares are illiquid. Some companies have repurchase rights that allow them to buy back your vested shares when you leave at the lower of FMV or your exercise price.
Check your equity agreement for post-termination exercise windows. For ISOs, you typically have 90 days to exercise after leaving. Missing this window converts ISOs to NSOs (losing the tax advantage) or they expire. If you're planning to leave a startup, put your ISO exercise deadline on your calendar the day you give notice.