The short version
Contribute in three steps. Step 1: put in at least enough to capture the entire employer match — that is free money with an instant return. Step 2: work toward 10–15% of your salary including the match, held over your career. Step 3: if your budget allows, pace your contributions to hit the 2026 IRS cap ($24,500 under 50, $32,500 at 50+, $35,750 at ages 60–63) without maxing out too early in the year. Run your own numbers in the 401(k) contribution calculator before you set your elections.
Step 1: capture the full employer match
This one is non-negotiable, and it is where the confusion lives — because match formulas read like riddles. Every match has two numbers: a rate and a cap. "50% up to 6% of salary" means the employer adds 50 cents for every dollar you contribute, but only on your first 6% of salary. You must contribute the full 6% yourself to get the full 3%-of-salary match. Contribute 4% and you leave part of the match unclaimed; contribute 10% and you do not earn a penny more than the cap allows.
The match is an instant, guaranteed return before the market does anything — a 100% match on your first 6% doubles that money the moment it lands. Over 35 years, a $4,500-a-year match at 7% compounds to roughly a quarter of a million dollars, costing you nothing beyond the contribution that unlocked it.
Step 2: aim for 10–15% of salary, match included
Once the match is captured, the standard guidance from financial planners is 10–15% of gross salary including what your employer adds, saved over the course of your career. So if you contribute 10% and your employer matches 3%, your combined 13% sits comfortably inside the band.
If 15% is out of reach today, use the 1%-a-raise trick: bump your contribution rate one point with every raise. Your take-home still rises, and a 10% rate quietly becomes 15% in five raises. If you start late (mid-30s or 40s), lean toward the top of the band — you have fewer years of compounding ahead.
Step 3: pace to the 2026 IRS cap — without maxing out too early
For 2026, the IRS caps your own elective deferrals at $24,500 if you are under 50, $32,500 at age 50+, and $35,750 at ages 60–63 (the SECURE 2.0 "super catch-up"). One note for high earners: since 2026, catch-up contributions must go into the Roth 401(k) if your prior-year wages topped the IRS threshold — roughly $150,000.
To check whether you are on pace to max out, use this per-paycheck math: (limit − contributed so far) ÷ remaining paychecks. But do not front-load the whole thing in January. If you hit the cap by September, your October–December paychecks contribute nothing — and many plans only match on paychecks where you actually contribute. Unless your plan has a true-up (the employer reconciles the match at year-end), maxing out early forfeits months of match money.
The age-based scoreboard
Planners use rough balance targets as you go: about 1× your salary by 30, 3× by 40, 6× by 50, and 8–10× by 60. Checkpoints, not verdicts — salaries grow, markets wobble, life happens. The calculator's milestone track plots your projected balance against these targets so you can see which ones your current rate clears.
Roth or traditional? One paragraph
Your contributions do not have to be pre-tax. A Roth 401(k) takes after-tax dollars now and grows tax-free; traditional takes pre-tax dollars now and you pay tax in retirement. The crude rule: Roth if you expect a higher tax rate in retirement, traditional if you expect a lower one. Most people split. The Roth vs Traditional 401(k) calculator runs the comparison with your numbers, and the retirement number calculator shows the 25× spending target behind it all.
Worked example: 30, earning $75,000, contributing 10%
Meet the classic case: age 30, $75,000 salary, $20,000 already in the 401(k), contributing 10% with a 100% match on the first 6% of salary. Year 1: your 10% is $7,500 — $288.46 per biweekly paycheck — and the employer adds 100% of your first 6% ($4,500). Total in the first year: $12,000.
Held for 35 years with 7% returns and 3% annual salary growth, the balance reaches $2,572,347 at 65 — of which about $1.83 million is pure compound growth, roughly 71% you never contributed. Against the age targets it trails at 40 ($226,314 vs $302,381) and at 50 ($696,466 vs $812,750), but the compounding catches up by 60 ($1,707,743 vs $1,456,357). Time is doing more of the work than extra contribution points ever could.
Frequently asked questions
What percent of my salary should I contribute to my 401(k)?
Aim for 10–15% of gross salary including the employer match, held over your career. The floor is non-negotiable: contribute at least enough to capture the full match. If the full band is out of reach, start at the match floor and raise your rate one point with every raise.
Is it better to max out my 401(k) or invest in an IRA or brokerage?
The usual priority order: first, contribute enough for the full employer match; second, max an IRA ($7,000 in 2026) if eligible, since IRAs often offer more investment choice at lower fees; third, push the 401(k) toward the annual cap. A taxable brokerage account comes last — after the tax-advantaged space is full — unless you need the money before age 59½.
Does my employer's match count toward my personal contribution limit?
No. The $24,500 limit (2026) covers only your own elective deferrals. Employer matches count toward a separate combined annual additions ceiling ($72,000 in 2026, plus any catch-up you are eligible for). A generous match never eats into your personal contribution room.
What happens if I contribute too much to my 401(k)?
You create an excess deferral. Withdraw the excess plus its earnings before the tax filing deadline and you are taxed on it once. Miss the deadline and it is taxed twice — once when earned, again when withdrawn. Ask payroll to cap your elections at the IRS limit.
What are the 2026 401(k) contribution limits?
$24,500 for employees under 50; $32,500 at age 50+ (the $8,000 catch-up); $35,750 at ages 60–63 (the $11,250 super catch-up). High earners above roughly $150,000 in prior-year wages must make catch-up contributions to the Roth 401(k). Limits adjust for inflation each year, so confirm with your plan documents.
Do I need to contribute every paycheck to get the full match?
Usually, yes — most plans match per paycheck, so months with zero contribution earn zero match. That is why maxing out the IRS cap too early in the year can backfire: once you hit the cap, later paychecks contribute nothing and earn no match. Ask your plan administrator whether the plan has a true-up — a year-end reconciliation that pays the match you would have earned. Without one, spread contributions evenly across the year.
More money math
The contribution rate is set — now optimize the tax side with the Roth vs Traditional 401(k) calculator, or check the destination with the retirement number calculator.