Vesting is the calendar that turns a promise into property. When you get a stock grant or an employer 401(k) match, you often do not own all of it right away. Instead it vests, meaning a slice becomes permanently yours on each scheduled date. Leave before a date and you forfeit whatever has not vested.
A vesting schedule spells out those dates. The most common one for stock is four years with a one-year cliff: nothing for twelve months, then 25% at the one-year mark, then the rest in equal monthly or quarterly pieces. Some companies front-load (more in year one) and a few back-load (more in year four). For 401(k) matches, schedules run from immediate to six years.
Why it matters: your real yearly pay depends on the schedule, not the headline number. A $120,000 grant that vests 10/20/30/40 pays $12,000 in year one and $48,000 in year four. The same grant vesting evenly pays $30,000 every year. Those are different jobs.
The common mistake is timing a resignation without checking the calendar. Leaving two weeks before a quarterly vest can cost thousands. Before giving notice, look at what vests in the next 30 to 90 days and decide whether it is worth waiting for.