Pre-tax, Roth or Taxable?

How much an investment outside your 401(k) has to earn to keep up with the tax break inside it.

Rules last verified Sep 25, 2026

These are example numbers. Answer a few questions and every calculator fills in with yours, saved in this browser.

Amount to invest this year

Years to retirement

Expected return

Fees

401(k) fund fees

Check your plan’s fund menu

Taxable fund fees

e.g. a broad index fund

Tax rates

Your tax bracket now

24% federal + 5% state = 29%

Example rates; set up your plan to fill in yours

Expected rate in retirement

Dividend yield

Cap gains + NIIT + state

Break-even return

Outside the 401(k), you’d need to earn 7.81% a year to match it

That’s 0.81 points a year more than the same 7.0% funds earn inside the plan, even after its 0.50% fees. If your plan’s funds cost 1.00%, the bar drops to 7.27%.

Pre-tax 401(k)

$35,242

After 27% tax on withdrawal

Roth 401(k)

$34,277

$7,100 after tax today, tax-free later

Taxable brokerage

$29,537

After dividend and capital-gains tax

What you’d keep, after all taxes

$10,000 of salary, 7% return

After-tax value by year
Point	Pre-tax 401(k)	Roth 401(k)	Taxable
Now	$7,300	$7,100	$7,100
5 yr	$10,002	$9,728	$9,245
10 yr	$13,703	$13,328	$12,196
15 yr	$18,774	$18,260	$16,258
20 yr	$25,723	$25,018	$21,847
25 yr	$35,242	$34,277	$29,537

Pre-tax or Roth comes down to one comparison

Your rate now (29%) against your rate in retirement (27%). Lower later means pre-tax wins.

In your cash flow

Putting $10,000 into the pre-tax 401(k) lowers take-home pay by only $7,100. The other $2,900 is tax you don’t pay this year. See it in My Plan →

Educational estimate. Assumes the same investments in every account, dividends taxed yearly and reinvested, and gains taxed when sold at the end. Roth invests the after-tax amount of the same salary. Returns are not guaranteed.