What Is a Pretax Contribution? How It Works and Example

What Is a Pretax Contribution?

A pretax contribution defers taxes until withdrawal, which is typically during retirement. For example, if you set aside $10,000 of your salary to contribute to a traditional 401(k) plan in 2024, you don't have to pay income taxes on that $10,000 of income in 2024. You will need to pay taxes on it when you withdraw funds (contributions, earnings, and any employer match) during retirement, whether that's 2034, 2044, or 2074.

This is in contrast to both aftertax contributions and Roth contributions. Several tax-advantaged accounts allow pretax contributions, including traditional (not Roth) 401(k)s and Individual Retirement Account (IRA)s, as well as 403(b) and 457 plans.

Pretax vs. Aftertax Contributions

If a contribution is made with income for which an individual has already paid tax, it is referred to as an aftertax contribution. This is different from pretax and Roth contributions. (See more about Roth contributions below.)

With an aftertax contribution, you deposit income into a traditional or Roth retirement account after paying taxes on it. Though there are no immediate tax breaks, the earnings on aftertax contributions grow tax-deferred until they are withdrawn.

Contributions to a traditional (non-Roth) retirement savings plan can be in the form of pretax and/or aftertax contributions. (However, Roth accounts also allow for aftertax contributions.) Aftertax contributions can be made instead of or in addition to pretax contributions.

This type of contribution is popular with high earners who have maxed out their 401(k) by contributing up to the limit with pretax or Roth contributions.

For tax year 2024, according to the Internal Revenue Service (IRS), if you're younger than 50 years old, the most you can contribute to a 401(k) is $23,000. If you're 50 or older, you can take advantage of an option to contribute an additional $7,500 in catch-up contributions. (For tax year 2023, you can contribute up to $22,500 if you're under 50, and an additional $7,500 if you're 50 or older.)

There is a limit on contributions from all sources, including employer contributions, every year. The tax year 2024 limit is $69,000 for people under 50, with an additional $7,500 for people age 50 and older.

Pretax vs. Roth Accounts

With a Roth account, such as a Roth 401(k) or Roth Individual Retirement Account (IRA), you pay taxes up front, in the year you make the contribution, so in retirement, you can withdraw the funds tax-free, as long as you've had the account for five years (in the case of a Roth IRA) and you're over age 59 ½.

If you are trying to decide whether to make pretax or Roth contributions, one strategy is to compare your current tax bracket with your expected tax bracket at retirement.

If you expect to be in a lower tax bracket at retirement, go the traditional route, and make pretax contributions. If you expect to be in a higher tax bracket at retirement, contribute to a Roth account instead. You're aiming to withdraw funds when your income tax bracket is the lowest, to reduce the taxes you'll need to pay.

However, you should also bear in mind that tax rules and brackets change over time. There's no way to truly know what the future holds, so take your best guess.

Tax Savings Example

Pretax contributions lead to tax savings.

For example, consider a married employee who earns $105,000 in gross income in tax year 2023. If their effective tax rate is 20%,their tax liability for the year will be 0.20 x $105,000 = $21,000, leaving the employee with $84,000 ($105,000 - $21,000) in take-home pay.

However, if that under-50 employee maxes out their 401(k) plan with a $22,500 pretax contribution, their taxable income will be reduced to $82,500 ($105,000 - $22,500), and their tax liability will be $16,500 (0.2 x $82,500), which is a savings of $4,500 ($21,000 - $16,500).

In calculating a pretax contribution, as this example shows, the amount of taxes withheld will be reduced as the basis for the taxable amount will be reduced.

The Bottom Line

Pretax contributions enable you to earmark funds for a retirement plan using income that has not been subject to payroll or income taxes.

Pre-tax contributions reduce your amount of taxable income now, which lowers your tax bill now. These taxes are deferred. You pay income tax on your contributions and earnings when you withdraw money from the account, which is typically during retirement.

If you have any questions about contributing to your retirement plan, talk to your human resources department or your plan administrator.