2024 401k Contribution Limit. In 2024, the contribution limit for a roth 401 (k) is $23,000, plus an additional contribution of $7,500 if you are age 50 or older. Employees can invest more money into 401 (k) plans in 2024, with contribution limits increasing from 2023’s $22,500 to $23,000 for 2024.

Those 50 and older can contribute an additional $7,500. Subtract from the amount in (1):