RawW7's answer is incorrect. The only contributions that are permitted to be made to a SIMPLE IRA are your elective deferrals to the SIMPLE plan made through your employer, employer contributions to the SIMPLE plan, and, after the 2-year holding period for the SIMPLE IRA has been completed, rollovers from another IRA or qualified retirement plan. The tax code explicitly prohibits you from making any other contributions, either deductible or nondeductible, to a SIMPLE IRA.
The limit for elective deferrals to a SIMPLE IRA is independent of the limit for making regular traditional IRA contributions to some other IRA.
