Can you contribute to both a SARSEP and Simple IRA plan? If so, what is the maximum contribution limit?

A SIMPLE IA may be the only active plan offered by an employer. The SIMPLE IRA replaced the SARSEP about 10 years ago however a SARSEP may still be operated if it had been in existance at the time and new participants may still be added. Just no new SARSEPS may be established. I don't see the point for continuing both even if you could. The SIMPLE IRA will acheive the same result generally speaking.

Presuming the plans are sponsored by unrelated employers, you may contribute to both. With one exception, each plan's own limits are followed, without regard to what one does in the other plan. The one exception is the section 402(g) limit, the elective deferral limit. The limit is an individual limit based on the person's tax year, which will virtually always be the calendar year. In general, persons under age 50 will have a $15,000 maximum allowable contribution limit, when adding elective deferrals made to the two plans.

…and individuals who are at least age 50 by year-end may defer an additional $5,000. ( $15,000 and $5,000 limits indexed as of 2007.