Here’s What Really Happens If You Put Too Much in Your 401(k)

Contributing to a 401(k) is one of the most effective ways to save for retirement. However, it’s possible to have too much of a good thing—that is, to exceed the annual limits set by the Internal Revenue Service (IRS), to contribute too much. When that happens, it can lead to penalties, potentially derailing your long-term financial goals. That’s why it’s important to know the annual 401(k) contribution limits and what to do if you accidentally overcontribute.

Maxed Out Your 401(k)—and Then Some? Here’s What That Means

An overcontribution is when you save more than the limit that’s set annually by the IRS. The limit depends on your age.

For 2025, the limits are $23,500 for individuals under 50 and $31,000 for individuals age 50 or older, including the up-to-$7,500 catch-up contribution. Those who are 60, 61, 62 or 63 have a higher catch-up contribution limit ($11,250).

“One of the most common reasons individuals find themselves overcontributing to their 401(k) is simply due to not regularly reviewing their retirement contributions,” said Remy Dou, CFP and co-founder of Retirement Planning Center Advisory Group.

And when you aren’t paying attention, those exciting moments in your career, such as promotions, pay raises, and bonuses, can unintentionally lead to an overcontribution.

“Over time, as people advance in their careers and receive salary increases, the percentage they initially set aside for contributions begins to represent a significantly larger dollar amount,” Dou said. “Mid-year raises or bonuses are especially common culprits. While many individuals are intentionally trying to maximize their retirement savings, a sudden increase in income can unexpectedly push them over the IRS limit without them realizing it. This scenario is also particularly common among state and local government employees who have access to both a 401(k) and a 457(b) plan. Without careful coordination, contributions across both plans can easily exceed allowable limits.”

The Consequences of Going Over the 401(k) Contribution Limit

Overcontribution can lead to several financial complications. Not only do you risk missing out on the intended tax benefits of retirement savings, but it can also trigger a series of penalties, including double taxation on the excess contribution.

“The penalties for overcontributing to a 401(k) can be significant,” Dou said. “Excess contributions, referred to as excess deferrals, must be removed by April 15 of the following year. If they are not withdrawn by this deadline, the amount will be taxed twice: once for the year it was contributed, and again when eventually withdrawn from the account.”

So the worst thing that can happen if you overcontribute to your 401(k) is that the overall value of your retirement savings will be reduced. This hinders your long-term retirement goals and limits the growth potential of your investments.

Overcontributed to Your 401(k)? Here’s How to Fix It

If you’ve realized that you’ve overcontributed to your 401(k), it’s wise to act quickly. The sooner you address any overcontributions, the more likely it is that you’ll avoid any long-term financial consequences and setbacks.

Identify the Excess Contribution

Review your 401(k) account and compare the total contributions made during the year with the IRS contribution limits.

Notify Your 401(k) Plan Administrator

Contact your plan administrator and inform them of the overcontribution.

“They can guide you through the process and typically provide a Corrective Distribution Request Form to begin withdrawing the excess,” Dou said. 

Withdraw the Excess Contribution

You must withdraw the excess contribution by April 15th of the following year. This requires you to complete Form 1099-R.

“If the correction is made before April 15 of the following year, the excess and any earnings can be properly reported without penalty,” Dou noted. “You’ll report the earnings on your Form 1040, and the following year, your 401(k) provider will issue a Form 1099-R to reflect the distribution and its earnings.”

Once you resolve your overcontribution, going forward, monitor your 401(k) contributions closely and try not to go over the limit again.

The Bottom Line

If you overcontribute to your 401(k), you’ll have to face the consequences. You can avoid double taxation by understanding the contribution limits and acting quickly if you overcontribute. This way, you’ll ensure that your 401(k) remains an effective tool for retirement. It’s important to track your contributions and make adjustments as needed to stay within IRS limits.