Under a 401(k) plan, the money you contribute from your own paycheck is always 100% yours, but employer contributions vest according to one of two federally capped schedules: a cliff of up to three years, where you own nothing until you hit the anniversary and then jump to full ownership, or a graded schedule of up to six years, where your ownership climbs in steps. Many employers use faster timelines or vest employer money immediately, and certain events force full vesting regardless of the schedule. The specifics live in your plan documents, and the difference between leaving a month too early and a month later can be worth thousands of dollars.
What Vesting Covers
Vesting is your legal ownership of the money your employer puts into your account. At 0% vested, you would forfeit every employer dollar if you left today. At 100%, all of it is yours to roll over or take with you. The percentages between represent the share you would keep on the way out.
None of this touches your own contributions. Every dollar you defer from your paycheck, whether traditional pre-tax or Roth, is 100% vested from the moment it lands in the account.1Internal Revenue Service. Retirement Topics – Vesting No schedule, policy, or termination can strip you of money you contributed yourself.
Cliff Vesting
A cliff schedule is all or nothing. You own 0% of employer contributions until you cross a specific service anniversary, and then you’re 100% vested overnight. Federal law caps that cliff at three years for 401(k) plans.2Office of the Law Revision Counsel. 26 USC 411 – Minimum Vesting Standards Some employers use a shorter cliff of one or two years; none can use a longer one.
The risk with a cliff is precision. Leave at two years and eleven months under a three-year cliff and you walk away with none of the employer money in your account. Hit the three-year mark and it all becomes yours.
Graded Vesting
A graded schedule spreads ownership across several years. You earn a set percentage each year, so an early departure still leaves you with something. The longest graded schedule federal law allows runs six years and looks like this:1Internal Revenue Service. Retirement Topics – Vesting
- Less than 2 years: 0% vested
- 2 years: 20% vested
- 3 years: 40% vested
- 4 years: 60% vested
- 5 years: 80% vested
- 6 years: 100% vested
Under this schedule, walking away at three years means keeping 40% of the employer contributions in your account. Employers can move faster than this, but not slower.
The Federal Ceiling on Employer Schedules
Three-year cliff or six-year graded is the outer limit. Employers can use anything more generous, including immediate vesting, a one-year cliff, or a three-year graded schedule. A plan that pushes past the federal limits risks losing its tax-qualified status, which creates serious tax consequences for the employer and every participant.3Internal Revenue Service. Fixing Common Plan Mistakes – Vesting Errors in Defined Contribution Plans
Safe Harbor Plans and the QACA Exception
Safe harbor 401(k) plans work differently. In a traditional safe harbor plan, employer matching and non-elective contributions must be 100% vested at all times, with no waiting period.4Internal Revenue Service. Issue Snapshot – Vesting Schedules for Matching Contributions The money is yours the day it’s deposited. Employers accept this in exchange for an exemption from certain nondiscrimination testing.
The exception catches people off guard. A Qualified Automatic Contribution Arrangement, or QACA, is a type of safe harbor plan that automatically enrolls employees. QACA matching contributions do not require immediate vesting; they must be fully vested after no more than two years of service.4Internal Revenue Service. Issue Snapshot – Vesting Schedules for Matching Contributions If your employer runs a QACA, don’t assume the match is fully yours from day one.
Events That Force Full Vesting
Certain events override whatever schedule your plan uses and make you 100% vested immediately.
Plan Termination
If your employer terminates the 401(k) plan, every participant becomes fully vested in all employer contributions, regardless of years of service.1Internal Revenue Service. Retirement Topics – Vesting
Partial Plan Termination
A partial termination is often triggered when a significant share of the workforce leaves in a plan year. As a general guideline, the IRS considers a workforce reduction of roughly 20% or more. Every “affected employee” then becomes 100% vested, which generally includes anyone who left for any reason during the plan year of the partial termination and who still has an account balance.5Internal Revenue Service. Retirement Plan FAQs Regarding Partial Plan Termination If you were caught up in a large layoff, it’s worth checking whether this applied.
Normal Retirement Age
All employees must be 100% vested by the time they reach the plan’s normal retirement age.1Internal Revenue Service. Retirement Topics – Vesting The plan document defines that age, and it varies by employer. If you’re within reach of it, leaving early can cost you employer money you’d otherwise keep just by staying.
Coming Back to a Former Employer
Whether prior service still counts after a break depends on how long you were gone and whether you had any vested balance when you left. In general, prior years of service must be restored for vesting purposes once you complete a year of service after being rehired.6eCFR. 26 CFR 1.410(a)-5 – Year of Service; Break in Service The plan can hold off on counting the old service until you’ve put in that full year back, but then it picks up where it left off.
The exception is the “rule of parity.” If you were 0% vested when you left and the number of consecutive one-year breaks in service equals or exceeds your total prior years of service, the plan can permanently disregard the earlier time.6eCFR. 26 CFR 1.410(a)-5 – Year of Service; Break in Service Someone who worked two years under a three-year cliff, left with nothing vested, and stayed away for two or more years could return as a fresh hire for vesting purposes.
Part-Time Workers and the 500-Hour Rule
Most plans historically defined a “year of service” as 1,000 hours worked in a 12-month period.1Internal Revenue Service. Retirement Topics – Vesting Part-time employees could work for years without earning a single year of vesting credit.
The SECURE Act and SECURE 2.0 changed that. Long-term part-time employees now earn vesting service credit for each 12-month period in which they complete at least 500 hours. SECURE 2.0 also cut the participation eligibility threshold from three consecutive qualifying years to two, effective for plan years beginning after December 31, 2024.7Internal Revenue Service. Notice 2024-73 – Additional Guidance With Respect to Long-Term, Part-Time Employees For vesting purposes, only 12-month periods beginning on or after January 1, 2023, count under these provisions.
How to Check Where You Stand
Your Summary Plan Description spells out the exact vesting schedule, the percentages at each service milestone, and how the plan defines a year of service. Request a copy from your plan administrator or HR if you don’t have one on hand.
For a faster read, look at your individual benefit statement, usually available through the plan’s online portal. It typically shows two figures: total account balance and vested balance. The difference is what you’d forfeit by leaving today. If you’re weeks or months away from a cliff date or the next graded step, run the math before you resign. Staying a little longer is sometimes worth more than the raise at the new job.