401(k) employer match rules
Last updated August 2026
Short answer
The match is the closest thing to a guaranteed return in personal finance, and the rules around it are where plans differ most. Two people with the same salary and the same contribution rate can receive very different amounts.
Common formulas, and what they actually pay
| Formula | You contribute | Employer adds | Total into plan |
|---|---|---|---|
| 100% of first 3%, 50% of next 2% | 5% | 4.0% | 9.0% |
| 50% of first 6% | 6% | 3.0% | 9.0% |
| 100% of first 4% | 4% | 4.0% | 8.0% |
| 100% of first 6% | 6% | 6.0% | 12.0% |
| Non-elective 3% | 0% | 3.0% | 3.0% |
Read your plan document rather than assuming. A 50% match on 6% and a 100% match on 3% both deliver 3% of salary, but they require different contributions from you to get there.
The last row is a non-elective contribution: the employer pays it whether or not you contribute anything. It is less common, and it is the one case where doing nothing still earns something.
Vesting: when the money becomes yours
Your own deferrals are always immediately and completely yours. Employer contributions can carry a schedule.
Immediate vesting means the match is yours the moment it lands.
Cliff vesting gives you nothing until a date, then everything. A three-year cliff means leaving at two years and eleven months forfeits the entire employer balance.
Graded vesting releases it in slices, commonly 20% a year over five years, so you keep a proportion if you leave partway.
Vesting only ever applies to employer money. Investment growth on employer contributions generally follows the same schedule as the contributions themselves.
The front-loading trap, and true-ups
Most plans calculate the match per paycheck. Contribute nothing in a given period and there is nothing to match for that period, and it is not recovered later.
So someone maximizing early can lose out. Defer aggressively, hit $24,500 in September, and your deferrals stop for the last three months, along with any match those months would have carried.
A true-up provision fixes this by recalculating the match on your full-year contributions after year end and paying any shortfall. Many plans include one. Many do not. It is a single question to your HR or plan administrator and it decides whether front-loading is free or expensive.
Where the match goes when you contribute Roth
If you make Roth deferrals, the employer match has historically gone into the traditional, pre-tax side of your account. Some plans now allow Roth matching, in which case the match is taxable to you in the year it is made.
Either way, most Roth 401(k) savers end up holding two pots inside one plan, taxed differently on withdrawal. That is normal and not a problem, but it is worth knowing so the eventual tax picture is not a surprise.
Try it in Walnut
Walnut connects to the brokerage accounts you hold outside the plan and reads the positions, so your workplace savings and everything else can be seen as one allocation.
Three questions worth asking your plan
What is the exact formula? Not "we match 5%", which is ambiguous, but the precise percentages and thresholds.
What is the vesting schedule, and where am I on it? This is worth real money when you are considering a job change, and it is knowable in advance.
Is there a true-up? The answer changes whether you should spread contributions evenly across the year.
A worked example of vesting
Suppose you earn $80,000, contribute 5%, and your employer matches 4% of pay, so $3,200 a year. The plan uses graded vesting at 20% a year over five years.
After two full years, $6,400 of employer money has landed and you are 40% vested, so $2,560 is yours. Leave now and you forfeit $3,840. Stay one more year and you are 60% vested on a larger balance. That difference is real compensation, and it is knowable before you accept another offer.
Two details worth confirming rather than assuming. Vesting is usually measured in years of service, which your plan may define by hours worked rather than calendar time. And investment growth on employer contributions generally vests on the same schedule as the contributions that produced it.
What happens to forfeited money
Unvested employer contributions you leave behind do not go back to the company as profit. They go into a plan forfeiture account and are typically used to reduce future employer contributions or to pay plan administrative expenses.
This matters mainly because it explains why plans have vesting schedules at all: they are a retention tool whose cost is borne by leavers and whose benefit flows to the plan. It is worth knowing so the schedule reads as a term of employment rather than an accounting quirk.
Sources
Contribution limits are from IRS Notice 2025-67. Vesting requirements and plan rules are set out by the US Department of Labor. Your own plan document is the authority on your formula. Walnut is informational and is not an investment adviser. This guide is educational and not personalized tax or investment advice; anything with a tax consequence is worth confirming with a tax professional.
FAQ
How does a 401(k) employer match work?
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Your employer contributes alongside you, based on what you defer. A typical formula is 100% of the first 3% of pay plus 50% of the next 2%, which pays 4% of salary to someone contributing 5%. If you contribute nothing, you receive nothing, which is why the match is the reason to contribute at least to the threshold.
What does vesting mean for my 401(k) match?
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Vesting is how long you must stay before employer contributions become permanently yours. Your own deferrals are always 100% yours immediately. Employer money may vest on a cliff, all at once after a set period, or gradually in slices. Leave before you vest and the unvested portion is forfeited.
Does the employer match count toward my contribution limit?
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No. The $24,500 employee limit for 2026 covers only your own deferrals. Employer contributions are additional and count toward a separate, much higher combined limit on everything going into the plan for you in a year.
Can I lose my employer match by contributing too fast?
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Yes, in plans that match per paycheck without a true-up. Hitting the annual limit in September stops your deferrals, and with no deferral there is nothing to match for the remaining months. A true-up provision reconciles this after year end, but not every plan has one.