Where do I deduct the $15,000 of retired military pay on MD tax return?

To get the deduction in the Maryland state return you will have to make sure that you selected "Active or reserve military retirement" on the "Where is your distribution from?" screen right after you enter your 1099-R during the federal interview. TurboTax will automatically give you the $15,0000 deduction on the state return if you are at least 55 years old on the last day of the taxable year (otherwise it will be $5,000) .

1. Login to your TurboTax Account 
2. Click on "Search" on the top right and type “1099-R”
3. Click on “Jump to 1099-R”
4. Enter your 1099-R information
5. Select "Active or reserve military retirement" on the "Where is your distribution from?" screen