The IRA/SEP/SIMPLE box being marked on the Form 1099-R provided by the payer indicates a distribution from an IRA. No other code is permitted to accompany the code 7 in box 7.
"However it says I must add a letter A-M and I am not sure which one to check"
What is "it?" Codes A and M are not permitted to be in box 7 for a distribution from an IRA.
Are you asking in regard to something needed on a state tax return?
