What is the difference between Traditional and Roth 401(k)?

Traditional 401(k) contributions are pre-tax: they lower your current taxable income and are taxed on withdrawal. Roth 401(k) contributions are after-tax, with no upfront deduction, but qualified withdrawals are tax-free.

Does my employer match go into the Roth 401(k)?

Usually not. Most plans put employer matching contributions on the Traditional (pre-tax) side no matter how you contribute, and you'll owe income tax on those funds when you withdraw them. Since SECURE 2.0, a plan may let you take the match as Roth instead, in which case the match counts as taxable income in the year it's made. Check your plan documents.

What is the 401(k) contribution limit for 2025?

The employee deferral limit is $24,500 for 2026. Workers aged 50+ can add $8,000 in catch-up contributions, and workers aged 60-63 get an enhanced catch-up of $11,250 instead under SECURE 2.0. The total limit including employer contributions is $72,000.

Can I split contributions between Traditional and Roth 401(k)?

Yes. Most plans allow you to allocate any percentage to each type. A common strategy is to go heavy Roth early in your career when your tax rate is low, then shift to Traditional during peak earning years.

Does Roth 401(k) have Required Minimum Distributions?

Not anymore. SECURE 2.0 removed RMDs from Roth 401(k)s starting in 2024, so they now match Roth IRAs. Before 2024, Roth 401(k)s were subject to RMDs, which is why older advice says to roll them into a Roth IRA before RMD age.

Traditional 401(k) vs Roth 401(k): Which Is Right for You?

US retirement accounts showing 401(k), Traditional IRA, and Roth IRA balances — A couple's 401(k)s, IRAs, Roth IRAs, HSAs and taxable accounts in one list.

Most employers now offer both Traditional and Roth 401(k) options. Both let you save up to $24,500 per year (2026 limit), and both receive employer matching. The tax treatment is opposite, so your choice decides whether you pay tax now or in retirement. The IRS 401(k) plans page covers contribution limits, employer matching rules, and the distinction between Traditional and Roth designations.

The Fundamental Difference

Traditional 401(k): Contributions are pre-tax. Your taxable income drops by the amount you contribute. The money grows tax-deferred, and you pay ordinary income tax on every dollar you withdraw in retirement.

Roth 401(k): Contributions are after-tax. Your take-home pay is lower because you don’t get the upfront tax break. But all growth and qualified withdrawals are tax-free.

Employer match: In most plans, your employer’s matching contributions go into the Traditional (pre-tax) side regardless of which you choose. Even if you contribute 100% to the Roth 401(k), the match is usually pre-tax. SECURE 2.0 lets plans offer a Roth match, but not every plan does.

Contribution Limits (2025)

Employee deferral: $24,500 (Traditional, Roth, or any split)
Catch-up (ages 50+): Additional $8,000
Enhanced catch-up (ages 60–63): $11,250 instead of $8,000, under SECURE 2.0
Total limit (employee + employer): $70,000

The employee deferral limit is the same for Traditional or Roth. You aren’t contributing “more” to the Roth, but Roth dollars are worth more because every dollar withdrawn is fully yours.

When Traditional 401(k) Wins

High Current Tax Rate, Low Expected Retirement Rate

If you’re earning $200,000 in the 32% bracket and expect retirement income of $80,000 in the 22% bracket, every Traditional 401(k) dollar saves you 32 cents in tax today and costs 22 cents later. That’s a 10-cent spread on every dollar, compounded over decades.

State Tax Arbitrage

Working in California (13.3% top rate) but retiring in Florida (0%)? Traditional contributions get both the federal and state deduction at the high rate, and retirement withdrawals in Florida owe no state tax.

Cash Flow Constraints

The Traditional option lowers your current tax bill, increasing take-home pay. If you need the cash flow to max out contributions, Traditional lets you save the full $24,500 with less impact on your paycheck.

Near Retirement

If you’re 5–10 years from retirement and in peak earning years, the Traditional deduction at your highest-ever marginal rate is hard to beat. There isn’t enough time for the Roth’s tax-free compounding to make up for the upfront cost.

When Roth 401(k) Wins

Low Current Tax Rate, Higher Expected Retirement Rate

Early in your career at $50,000 (12% bracket), Roth contributions lock in a low rate. If your retirement income ends up in the 22% bracket (from RMDs, Social Security, pensions), the Roth dollars are already tax-free.

Long Time Horizon

At age 25 with 40 years to retirement, the Roth’s tax-free compounding is worth a lot. A $24,500 Roth contribution at 7% annual return grows to about $367,000 in 40 years, all tax-free. The same Traditional contribution at 22% tax on withdrawal is worth about $286,000 after tax.

Tax Rate Uncertainty

If you believe federal tax rates will increase over the next 20–30 years (due to national debt, entitlement funding, or policy changes), the Roth locks in today’s known rate versus an unknown future rate. See our Roth conversion strategy guide for how to optimize conversions in low-income years.

Avoiding RMD Complications

Roth 401(k)s have had no RMDs since 2024 (SECURE 2.0), the same as Roth IRAs. Roth money doesn’t force taxable withdrawals in your 70s the way Traditional balances do, so a larger Roth share means smaller RMDs overall. Rolling to a Roth IRA is still an option if you want more investment choice.

Tax Diversification

If you’re already heavy on Traditional accounts, adding Roth lets you manage your tax bracket year by year in retirement.

The Split Strategy

You don’t have to choose one. Many plans let you split contributions, for example 60% Traditional and 40% Roth, which builds tax diversification.

A common approach:

Early career (22–35): Heavy Roth (low bracket, long compounding horizon)
Peak earning years (35–55): Heavy Traditional (highest marginal rate, biggest deduction value)
Pre-retirement (55–65): Split or Roth if income drops, Traditional if still in peak bracket

Employer Match and Taxes in Retirement

In most plans the employer match is pre-tax. If you contribute $24,500 to the Roth 401(k) and your employer matches $12,250, your account has:

Roth bucket: $24,500 (tax-free withdrawals)
Traditional bucket: $12,250 (taxable withdrawals)

So even a 100% Roth contributor usually has some Traditional balance to manage in retirement.

The Effective Contribution Argument

$24,500 in a Roth 401(k) is worth more than $24,500 in a Traditional 401(k) because the Roth dollars are after-tax. The Roth shelters more wealth within the same contribution limit.

If you’re in the 24% bracket, a $24,500 Traditional contribution is worth $18,620 after taxes at withdrawal. The same $24,500 Roth contribution is worth $24,500 at withdrawal, a 31% higher effective contribution.

This matters most for high earners who already max out contributions.

How cinder.fi Helps

This year’s contribution room for IRAs, 401(k) deferrals and HSAs for a married couple — This year's IRA, 401(k) and HSA room for each spouse.

cinder.fi models Traditional and Roth 401(k) contributions as separate account buckets in your projection. It calculates the tax impact of each contribution type across your retirement, including the interaction with Social Security taxation, RMDs, IRMAA thresholds, and state taxes for all 50 states. Use the scenario comparison tool to run a Traditional-heavy plan against a Roth-heavy plan and compare lifetime after-tax income. The 401(k) and Roth retirement calculator shows both buckets on your own numbers.

Compare your options: try cinder.fi free.

April 2, 2026 · 4 min read