I get an annuity from the Civil Service Retirement System (CSRS). This is not an IRA. How do I answer the TurboTax of how much of this annuity was an RMD?

CSRS should compute your RMD so you will need to contact them so you can enter the correct entries into TurboTax.

For more information, refer to the IRS FAQs Retirement Plan and IRA Required Minimum Distributions FAQs.  You can also review the TurboTax article What is an RMD?

 Refer to the TurboTax article Why don't I have an RMD listed on my 1099-R?