How do I enter codes 1B, B1 and M1 from 1099-R forms?

[SteamTrain]

If you are referring to box 7 on a 1099-R.  Three 1099-R forms?

Those are actually two codes....

a B and a 1

a 1 and a B

an M and a 1

______

Each is put in as a separate box 7 entry (two boxes are provided in the software form)

The order of B & 1 vs 1 & B is probably not important.

[MonikaK1]

You can have up to two distribution code entry fields in box 7. If you see more than one letter or number in box 7, check the box, "I have more than one value in Box 7" to open another entry field to enter the second code. The order doesn’t matter.

Enter the Form 1099-R exactly as received by entering both codes 1 and B together in one box. These two codes together indicate that you made a distribution from a Roth account in a qualified retirement plan before age 59½, not a distribution from a Roth IRA. 

Entering codes M and 1 together means there was a loan taken from the account that wasn't fully repaid. See this thread for a discussion on this topic. 

Enter the 1099-R and answer the follow-up questions to determine the actual taxable amounts.

See this article for more information from TurboTax regarding Form 1099-R.

See here for more information from IRS on Form 1099-R, or contact your payer for more details.