2025 401k Limits 401k Changes. If you're already investing in a 401(k), or if you want to start, you should be aware that some key irs changes are going into effect in 2025. If you plan to adjust 401(k) deferrals for 2025, now is the time to be doing it, valega said.

Employee contribution limits go up $500 more in 2025, to $23,500 from $23,000. Key changes for 2025 retirement plan contribution limits.