If you leave a job before you’re fully vested in your 401(k), you keep 100% of what you contributed from your paycheck plus any growth on it, and you forfeit some or all of the employer’s matching or profit-sharing contributions based on your plan’s vesting schedule. Your own deferrals are nonforfeitable from day one under federal law.1U.S. Department of Labor. Employee Retirement Income Security Act (ERISA) The employer-funded portion is the only piece at risk, and how much of it you walk away with depends entirely on where you sit on the vesting timeline the day you leave.
What You Keep and What You Lose
Two pools of money live inside your 401(k), and the plan administrator tracks them separately.2U.S. Department of Labor. FAQs About Retirement Plans and ERISA The first is everything you deferred from your paycheck, plus investment gains on it. That pool is yours no matter when you leave. If you put in $15,000 over two years and it grew to $17,500, the full $17,500 goes with you.
The second pool is employer money: matching contributions, profit-sharing deposits, and growth on those amounts. This pool follows the vesting schedule. If the employer contributed $10,000 and you’re 40% vested when you quit, you keep $4,000 and the remaining $6,000 is forfeited. At 0% vested, the whole employer-funded balance goes back, no matter how large it has grown.
Forfeited dollars don’t return to the company’s operating account. Federal rules limit forfeitures to three uses: paying the plan’s administrative costs, reducing future employer contributions, or being reallocated to other participants. Plans must apply forfeitures within 12 months after the close of the plan year they arise in. The money stays inside the retirement plan.
The Vesting Schedules Your Employer Can Use
Federal law caps how long an employer can make you wait to fully own matching contributions. For a 401(k), the tax code allows two structures, and your plan will use one of them or something faster.3Office of the Law Revision Counsel. 26 USC 411 – Minimum Vesting Standards
Cliff Vesting
Under cliff vesting, you own 0% of employer contributions until you complete three years of service, then jump straight to 100%. No partial credit. Leaving at two years and eleven months forfeits every dollar the employer contributed. Staying one more month keeps all of it. Timing is everything.
Graded Vesting
Graded vesting phases in your ownership over up to six years. The slowest schedule federal law permits is:3Office of the Law Revision Counsel. 26 USC 411 – Minimum Vesting Standards
- 2 years of service: 20% vested
- 3 years: 40%
- 4 years: 60%
- 5 years: 80%
- 6 or more years: 100%
Employers can be more generous. Some vest immediately, others use a two-year cliff or a faster graded track. The exact schedule that applies to you lives in your plan’s summary plan description, and it’s worth pulling before you resign.
A “year of service” for vesting purposes generally means at least 1,000 hours of work in a 12-month period. That threshold can matter if you’ve moved between full-time and part-time status.
When You’re Fully Vested No Matter What the Schedule Says
A few situations override the schedule and make every employer dollar yours immediately.
The Plan Is Terminated
If your employer shuts down the 401(k) plan, every participant becomes 100% vested in all employer contributions on the termination date, regardless of tenure.4Internal Revenue Service. Retirement Topics – Termination of Plan Matching, profit-sharing, all of it. The employer can’t wind down the plan and keep unvested money on the way out.
A Partial Plan Termination
A large layoff can trigger a partial plan termination. The IRS’s general guideline is that if roughly 20% or more of plan participants lose their jobs in a year, the event may qualify.5Internal Revenue Service. Retirement Plan FAQs Regarding Partial Plan Termination When that happens, affected employees must be 100% vested in employer contributions as of the termination date. Many workers who were part of a big reduction in force never learn this and leave money on the table. If you were laid off in a wave, ask.
Safe Harbor Contributions
Traditional safe harbor 401(k) plans vest all safe harbor contributions immediately, including the standard 3% nonelective contribution and the basic safe harbor match. Plans using a qualified automatic contribution arrangement (QACA) can put safe harbor contributions on a two-year cliff instead. Your plan documents will say which design applies.
Cashing Out Instead of Rolling Over
Once the unvested portion is forfeited, what remains is yours to move. Taking it as cash is expensive. The plan withholds 20% for federal taxes upfront, but that’s only a deposit against your actual bill. The full distribution gets added to your taxable income for the year.6Internal Revenue Service. 401(k) Resource Guide – Plan Participants – General Distribution Rules
If you’re under 59½, add a 10% early withdrawal penalty.7Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions On a $20,000 cash-out, that’s $2,000 in penalty before income tax. Between withholding, penalty, and your regular bracket, a third or more can disappear. Most state income taxes take another slice.
Some exceptions waive the 10% penalty, including certain medical expenses, disability, and IRS levy. Quitting a job before 59½ isn’t one of them, with a narrow carve-out: if you separate from service during or after the calendar year you turn 55, distributions from that plan can escape the penalty (the “Rule of 55”).7Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions
A direct rollover from the old plan into an IRA or a new employer’s plan avoids the 20% withholding entirely because the money never passes through your hands. For a vested balance under $1,000, the plan can cash you out automatically. For balances between $1,000 and $7,000, the plan can automatically roll you into an IRA it chooses if you don’t give instructions (SECURE 2.0 raised this ceiling from $5,000 to $7,000 for distributions made after December 31, 2023). Above $7,000, the plan generally has to leave you alone until you decide what to do.
If You Have an Outstanding 401(k) Loan
An unpaid 401(k) loan turns into a problem quickly after you leave. Most plans demand full repayment shortly after termination. If you can’t pay, the unpaid balance is treated as a distribution, with income tax and possibly the 10% penalty attached.8Internal Revenue Service. Retirement Topics – Plan Loans
There is relief built into the tax code. When the plan reduces your account balance to offset an unpaid loan, that’s a plan loan offset, and it counts as an eligible rollover distribution. If the offset happened because of plan termination or your separation from service, it’s a “qualified plan loan offset,” and you have until your tax filing deadline for that year, including extensions, to roll the offset amount into an IRA or another eligible plan.9Internal Revenue Service. Plan Loan Offsets You can put the money in from any source and report the rollover on your return. Miss the deadline and the offset becomes taxable for the year.
Coming Back to the Same Employer Later
If you leave and return to the same company within five years, federal rules generally require the plan to preserve your prior service credit.2U.S. Department of Labor. FAQs About Retirement Plans and ERISA Two years into a six-year graded schedule when you quit, back three years later, and those first two years should still count. You wouldn’t restart from zero.
Longer absences can erase the credit, and the exact break-in-service rules live in your plan document. Ask the plan administrator before assuming your old years survived the gap. If you’re close to a vesting cliff, running the math on staying a few more months against leaving and hoping to reclaim credit can change the decision.