Box 4 of your Form 1099-R shows the federal taxes withheld from your RMD. Here's how to enter your 1099-R into TurboTax: https://ttlc.intuit.com/community/entering-importing/help/where-do-i-enter-my-1099-r/00/26339
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
