The qualified retirement plan contribution credit is available only if a taxpayer lived in one or more other states that taxed contributions into qualified retirement plans at the time they were made. The taxpayer must be vested in the other state's retirement plan at the time of residing in the other state. Qualified retirement plans are retirement plans defined in I.R.C. 401, 403, 408 and 457, and all public employee retirement plans of the federal, state and local governments, including military retirement.
The credit is claimed each year in an amount based on the taxpayer's life expectancy at the time the taxpayer first claims the South Carolina retirement income deduction. The life expectancy table is available in Appendix C of Publication 590 available at www.irs.gov.
The total credit is limited to the amount of contributions taxed each year multiplied by 7% (South Carolina’s highest marginal rate for individual income tax).