Based on 401(k) Resource Guide at IRS.gov, the combined total contribution you can make to all of your 401(k) plans (including traditional 401(k), Roth 401(k), and individual 401(k) plans) in 2013 increased by $500 to $17,500. The catch-up contribution limit stays the same at $5,500. However, you may be limited by what your employer allows you to contribute. For example, if your salary is $40,000 per year and your employer only allows up to 20% of your salary to be used for your 401(k) contribution, then your maximum is $8,000. Otherwise, the maximum legal limits allowed by the IRS are shown below.
401(k) Maximum Contribution Limit
401(k) Catch-Up Contributions
Rules for Multiple 401(k) Plans
If you participate in more than one 401(k) plan —
i.e. a Roth 401(k) and a Traditional 401(k), or plans from multiple employers — the above 401(k) limits apply to the total amount regardless of the number of plans you participate in. The limits apply to your total combined contributions; your combined contributions across all plans cannot exceed the above limits.
Employer Contribution Limit and Matching Contribution
For self-employed business owners who participate in an Individual 401(k) plan (also known as Solo 401(k)), there is an additional piece of information that you must be aware of: With an Individual 401(k) plan, you can contribute the Employee portion out of your salary, and in addition, your company can contribute up to 25% of your W2 wages up to the Maximum Employer Contribution below.