An employer match is the closest thing to free money most people will see. But the match comes with rules: a formula for how much you have to put in, a schedule for when it shows up, and a vesting schedule that decides how much of it you keep if you leave. Here is how all three work, using one person’s numbers.
The setup
Say Dana earns $70,000 a year, paid every two weeks, so 26 paychecks of about $2,692. Her employer’s plan matches “50% of the first 6% of pay.” That phrase is the most common way match formulas are written, and it trips people up.
It does not mean the employer puts in 6%. It means the employer matches half of whatever Dana contributes, up to 6% of her pay. So:
- If Dana contributes 3% ($2,100 a year), the employer adds 1.5% ($1,050).
- If she contributes 6% ($4,200), the employer adds 3% ($2,100).
- If she contributes 10% ($7,000), the employer still adds 3% ($2,100). Nothing above 6% gets matched.
The number Dana needs to know is 6%. Below that, she leaves money on the table. At 3% she is giving up $1,050 a year, which over a 30-year career, before any investment growth, is more than $30,000.
Other formulas you’ll see include “100% of the first 3%, then 50% of the next 2%” (which pays 4% if you contribute 5%) or a flat “dollar for dollar up to 4%.” The method is the same: find the contribution rate where the match stops growing, and get to at least that rate.
The front-loading trap
Now say Dana gets a raise and decides to max out her 401(k) for 2026. The IRS limit for employee contributions in 2026 is $24,500. She wants to hit it fast, so she sets her contribution to 40% of each check.
At about $1,077 per check, she reaches $24,500 by her 23rd paycheck. For the last three or four checks of the year, she contributes nothing. And here is the problem: many plans calculate the match each pay period. No contribution in a pay period means no match for that period.
Those last checks could have earned her about $81 each in match money (3% of $2,692). Lose four of them and she has given up around $320.
Some plans fix this with a “true-up,” a year-end calculation that tops up the match to what you would have received if you had contributed evenly. If your plan has a true-up, front-loading is fine. If it doesn’t, spread your contributions so you hit the limit with your last paycheck of the year. The plan’s summary plan description will say which way it works, or HR can tell you in one email.
If you are 50 or older, the 2026 catch-up is an extra $8,000, and people aged 60 to 63 can add up to $11,250 instead. Whether the employer matches catch-up money depends on the plan.
Vesting: the match isn’t fully yours yet
Every dollar Dana contributes from her own paycheck is hers immediately. That’s the law. The employer’s match is different. The employer can make it “vest,” or become hers, over time.
Federal rules limit how slow that can be for matching contributions. The plan must be at least as generous as one of these:
- Cliff vesting: 0% until you complete three years of service, then 100%.
- Graded vesting: 20% after two years, then 20% more each year, reaching 100% after six years.
Many employers are faster than that, and some vest the match immediately. “Safe harbor” 401(k) plans generally must vest safe harbor matching contributions right away.
Back to Dana. Say her plan uses the six-year graded schedule, she has worked there for three years and four months, and her match account holds $6,500. If she leaves today, she is 40% vested and walks away with $2,600 of the match. The other $3,900 goes back to the plan. If she can stay until her four-year anniversary, she moves to 60% vested and keeps $3,900 plus whatever she adds in the meantime.
Using this when you change jobs
Before giving notice, log into the 401(k) site and look for the “vested balance” figure, which is often different from the total balance. Then look up your vesting date. If you are a few weeks from the next step, it can be worth asking for a later start date at the new job.
Pay attention to how the plan counts a “year of service.” Many plans count a year as any plan year in which you worked at least 1,000 hours, not the anniversary of your hire date. That can move your vesting date earlier or later than you expect.
And when comparing job offers, a 4% match that vests immediately is worth more to someone who changes jobs every two years than a 6% match with a three-year cliff. Ask about the vesting schedule during the offer stage, not after you sign.
This post is general information, not financial advice.