Employers that offer retirement plans can choose from several alternatives. A 401(k) allows employers and employees to make pre-tax contributions. The same is true for Savings Incentive Match Plan for Employees individual retirement account plans, often referred to as SIMPLE IRAs, but employers can’t adopt this type of plan if the company has more than 100 employees. Both plan types have contribution limits. As an employee, you might be in a position to contribute to both plans in the same year, but you must observe the joint contribution limits.

Two Plans, One Year

It might be unusual to belong to a 401(k) and a SIMPLE IRA in the same year. Employers can’t offer both at the same time, although they can make separate arrangements for employees covered by a collective bargaining agreement. Nonetheless, as an employee, you might be able to contribute to both plan types in one year if you change employers. Alternatively, your employer might replace one plan with the other during the year. A third possibility is that you work for two unrelated employers at the same time. If you belong to both types of plan in the same year, your total contributions can’t exceed the Internal Revenue Service limits on 401(k) plans.

401(k) Contribution Limits

As of 2014, the IRS limits employee pre-tax 401(k) contributions to $17,500 per year. The plan might allow you to make an additional, catch-up contributions of $5,500 if you’re age 50 or older, raising your annual contribution limit to $23,000. Your employer also can kick in pre-tax contributions to your account. The sum of your and your employer’s contributions can’t exceed 100 percent of your compensation or $52,000, whichever is less. If you’re age 50 or older, the limit is $57,500. If your employer contributes a set percentage of your compensation to your 401(k), it can only count the first $260,000 when figuring the amount.

SIMPLE IRA Contribution Limits

The IRS limit as of 2014 for employee contributions to a SIMPLE IRA is $12,000. That limit rises to $14,500 once you reach age 50. Employers have a few alternatives when figuring their contributions, but generally, the amount is between 1 and 3 percent of your contributions or 2 percent of the first $260,000 of your annual compensation. While some 401(k) plans allow employees to make nondeductible contributions, SIMPLE IRAs don’t permit this option.

Joint Contribution Limits

If you belong to a 401(k) and a SIMPLE IRA in the same year, your contributions to either plan count toward the overall limit of $17,500, or $23,000 if you've reached age 50. For example, if you contribute $12,000 in 2014 to your SIMPLE account, the most you can kick into your 401(k) is $5,500 or $11,000, depending on your age. Some employer plans prohibit catch-up contributions. Nonetheless, you can make joint contributions that include the catch-up limits. For example, suppose you contribute $17,500 to a 401(k) that doesn't permit catch-up contributions. If you've reached age 50, you can contribute up to $5,500 to your SIMPLE IRA to bring your total annual contributions to $23,000.