What Is the Max You Can Contribute to a 401k?

A 401(k) is an employer-sponsored retirement plan that allows workers to save and invest a portion of their paycheck before taxes. The Internal Revenue Service (IRS) sets annual limits on how much can be contributed, which is important for maximizing savings while following tax law. This article clarifies the maximum amounts you can contribute to your 401(k) for the 2025 tax year.

Employee Elective Deferral Limits

The most direct answer to how much you can contribute to a 401(k) is the employee elective deferral limit. For the 2025 tax year, the IRS has set this limit at $23,500. This cap applies to the combined total of any traditional pre-tax contributions and any Roth 401(k) contributions you make.

The tax code provides a way for those nearing retirement to save more. Individuals who are age 50 or over can make additional “catch-up” contributions, set at $7,500 for 2025. This allows an individual aged 50 to 59 to contribute a total of $31,000.

A new provision from the SECURE 2.0 Act, effective in 2025, introduces a higher catch-up limit for individuals aged 60, 61, 62, or 63. They can contribute an enhanced catch-up amount of $11,250, for a total of $34,750, provided their plan has been amended to allow it. For example, a 42-year-old employee can contribute a maximum of $23,500, while their 61-year-old colleague could contribute up to $34,750.

Starting in 2026, a separate rule will require catch-up contributions made by high-income earners—those with FICA wages over $145,000 in the prior year—to be directed into a Roth 401(k), if the plan permits.

The Overall Contribution Limit

Beyond what an employee contributes, a broader limit governs all money going into a 401(k) plan for a single year. This is the overall contribution limit, or the Section 415 limit, which is $70,000 for 2025. This amount includes the employee’s elective deferrals, any employer matching contributions, and other employer inputs like profit-sharing.

For instance, an employee under age 50 who contributes $23,500 to their 401(k) can also receive employer contributions. If their employer adds $40,000, the total of $63,500 is permissible because it is below the $70,000 overall limit.

Catch-up contributions are not subject to this $70,000 limit, allowing the total annual additions for an employee age 50 or over to exceed this cap. For example, if an employee aged 55 contributes their maximum of $31,000 (including their $7,500 catch-up), only their $23,500 regular contribution counts toward the $70,000 limit. Their employer could then contribute up to $46,500, bringing the total contribution to the account to $77,500. Plan administrators are responsible for ensuring that these total contributions do not exceed the Section 415 limit for any participant.

Contribution Rules for Multiple 401(k) Plans

Navigating contribution limits can become more complex for individuals who participate in more than one 401(k) plan during the year, often due to changing jobs. The employee elective deferral limit—$23,500 for 2025, plus any applicable catch-up amount—is a personal limit. This cap applies to the total contributions an individual makes across all 401(k) and 403(b) plans they participate in during the tax year. An employee cannot contribute the maximum to a 401(k) at an old job and another maximum amount to the plan at a new job in the same year.

In contrast, the overall contribution limit of $70,000 for 2025 is applied on a per-plan basis, meaning each employer’s plan has its own separate ceiling. For example, an employee under 50 who contributes $12,000 to Company A’s 401(k) can only contribute up to $11,500 to Company B’s plan in the same year. However, both Company A and Company B could make their own employer contributions to their respective plans, each subject to a separate $70,000 overall limit.

Correcting Excess Contributions

Accidentally contributing more than the elective deferral limit, which can happen when changing jobs, creates an “excess deferral.” It is the employee’s responsibility to identify this over-contribution and request a “corrective distribution” from the plan administrator to have the excess funds, plus any investment earnings, returned.

To avoid double taxation, the excess contribution and its earnings must be distributed from the plan by April 15 of the year following the over-contribution. For an excess contribution made in 2025, the withdrawal deadline is April 15, 2026. This deadline is not extended even if you file for an extension on your personal income tax return.

If the corrective distribution is completed on time, the excess deferral is included in your taxable income for the year it was contributed. The earnings on that excess are then reported as taxable income in the year they are distributed. If you miss the deadline, the excess amount is taxed when contributed and taxed again when eventually distributed.