CSRS is Civil Service Retirement System. Form 502 is Maryland Resident Income Tax Return. Subtractions from Income includes Pension Exclusion, which allows you to subtract some of your taxable pension and retirement annuity income.
To apply the Exclusion, two conditions must apply. One, on the last day of the tax year, you were age 65 and above orcompletely disabled or your spouse was completely disabled. Two, the taxable pension/annuity included on your federal return was from an 'employee retirement system'. Form 502 defines employee retirement system by what it isn't. It doesn't include an IRA (traditional, Roth), a Keogh Plan, a simplified employee plan (SEP), or an ineligible deferred compensation plan.
For more information, go to website for the Comptroller of Maryland/Revenue Administration Division at individuals.marylandtaxes.com.
You may contact Taxpayer Service in several ways. One, email at taxhelp@comp.state.md.us. Two, phone at 1-800-MD TAXES (1-800-638-2937) or (410) 260-7980. Three, mail at Comptroller of Maryland, Revenue Administration Center, Taxpayer Service Section, Annapolis MD 21411.