You may need to recheck the "Retirement and Social Security" topic to verify your entries. Sometimes you might need to first delete the entries and complete the topic interview and then go back and re-enter the information.
Taxable social security amounts on line 6b of your form 1040 are included on lines 1 and 11 of your MD form 502 but then are subtracted on line 15 of the form 502. In desktop versions you can see the forms in "Forms Mode."
In online versions you can see a MD tax summary using the steps below. The social security subtraction will be part of the "Subtractions from Income" line in the MD summary. You can also use the print center to download print your forms to see the calculations.
1. Select "Tax Tools" in the left hand menu
2. Select "Tools"
3. Select "View Tax Summary"
4. Select "Preview My 1040" in the left hand menu
5. Select "MD Tax Summary"
Did you enter your SSA1099 in the right place in the federal return? Information flows from the federal return to the state return. If you entered the Social Security in the wrong place, that might be why you are having trouble with MD. Maryland does not tax Social Security.
Look at your federal software:
Go to Federal> Wages & Income>>Retirement Plans and Social Security (SSA1099 and 1099RRB) to enter your SSA1099.