401(k) Contribution Limits, Matching, and Strategy for 2024

Most people treat their 401(k) like a set-and-forget account. They pick a contribution percentage when they're hired, occasionally look at the balance, and mostly try not to think too hard about it. This is a reasonable survival strategy but a bad wealth-building one. The people who come out of their working years with meaningful retirement savings make specific, deliberate choices about how much to contribute, when to change that amount, and what to do with the match.

The 2024 Numbers You Need to Know

The IRS limits how much you can contribute to a 401(k) each year. For 2024, the employee contribution limit is $23,000. If you're 50 or older, you get an additional "catch-up" contribution of $7,500, bringing your total to $30,500.

The total limit including employer contributions (match, profit sharing, etc.) is $69,000 for 2024 (or $76,500 with the 50+ catch-up). This is the combined ceiling for everything going into your account from all sources.

These limits are adjusted annually for inflation, usually by $500 increments. Check the IRS website at the start of each year if you're trying to max out.

The Match: The Only Guaranteed Return in Investing

If your employer offers a 401(k) match, contributing at least enough to capture the full match is the single highest-priority personal finance action you can take. A 50% match on up to 6% of your salary is an instant 50% return on those dollars before the investments do anything. No other legal investment comes close.

Common match structures:

• 100% match on first 3% of salary (contribute 3%, employer puts in 3%)
• 50% match on first 6% of salary (contribute 6%, employer puts in 3%)
• Dollar-for-dollar match up to a flat dollar amount

A 35-year-old earning $75,000 with a 50% match on up to 6% of salary: if she contributes 6% ($4,500/year), her employer adds 3% ($2,250). Over 30 years at 7% average annual returns, that employer match alone grows to approximately $227,000. It's free money with a time multiplier.

Traditional 401(k) vs. Roth 401(k): Which to Choose

If your employer offers both traditional and Roth 401(k) options, the same logic as the IRA decision applies: traditional gives you a tax deduction now but taxes withdrawals later; Roth takes after-tax contributions but grows tax-free.

One important difference from IRAs: Roth 401(k)s have no income limits for contributions, unlike Roth IRAs. High earners who can't contribute directly to a Roth IRA can use a Roth 401(k) instead.

A practical approach many financial advisors recommend: if you're early in your career and in a low tax bracket, prioritize Roth 401(k) contributions. If you're in your peak earning years at a high tax rate, traditional makes more mathematical sense. If you're genuinely unsure, splitting contributions between both hedges against future tax uncertainty.

How to Calculate Your Contribution Amount

If you want to max out your 401(k) at $23,000, and you're paid biweekly (26 pay periods), you need to contribute $884.62 per pay period. Most 401(k) plans accept contributions as a percentage of salary rather than a dollar amount — so you'd calculate: $23,000 ÷ your annual salary × 100 = the percentage you need to set.

At $85,000 annual salary: $23,000 ÷ $85,000 = 27.1%. That's a high bar. Most people don't max out immediately.

A more realistic starting point: contribute enough to get the full match, then increase by 1% of salary each year (many plans have an auto-escalation feature that does this automatically). Starting at 6% and adding 1% per year reaches 15% after 9 years — the contribution rate most retirement planning models suggest for on-track retirement savings.

Vesting Schedules: The Hidden Catch on Employer Contributions

Your contributions to a 401(k) are always 100% yours immediately. But employer contributions may be subject to a vesting schedule — meaning you only "own" them after a certain period of employment.

Cliff vesting: you own 0% of employer contributions until year 3 (or some other cutoff), then 100% immediately. Leave before the cliff and you lose all the match.

Graded vesting: you earn an increasing percentage each year (e.g., 20% per year for 5 years, so you're fully vested at year 5).

This matters enormously when you're considering leaving a job. If you're 18 months from being fully vested in a 3-year cliff vesting schedule and you've been getting generous employer matches, the unvested amount could be worth $15,000-30,000 or more. That number should factor into your decision to leave.

What Happens to Your 401(k) When You Leave a Job

You have four options: leave it with your former employer's plan (fine if the investment options are good and the plan has low fees), roll it over to your new employer's plan (if they accept rollovers), roll it over to a traditional IRA (gives you the widest investment options and often lowest fees), or cash it out (terrible choice — you'll owe income tax plus a 10% early withdrawal penalty if you're under 59½, potentially costing you 30-40% of the balance).

The rollover to an IRA is almost always the right move for most people. Use a direct rollover (the money goes from your old plan directly to your new IRA without touching your bank account) to avoid any withholding complications. Do it within 60 days if you do take possession of the funds — that's the IRS deadline to avoid it being treated as a distribution.