If the person who owned the account withdrew their RMD before they died, you do not have to take one for yourself in 2025. If they did not withdraw their RMD before they died, you must withdraw their RMD.
Remember that an RMD is the minimum amount someone must withdraw, it is not a special transaction. If the RMD was $5000, that could be satisfied by withdrawing $5000 in December, but it could also be satisfied by withdrawing $500 per month for 12 months for living expenses.
Their 2025 RMD is based on their age and the account balance as of 12/31/2024. You can get that from the broker. If they and you did not withdraw the RMD in 2025, you should withdraw it as soon as you can. Then when you file, you report that you missed the RMD, and ask for a waiver of the penalty. As part of the waiver request, you will say that you took the withdrawal in 2026 as soon as you learned the rules.
The actual withdrawal will be reported on your 2026 return since that is when it was taken.
Then separately, you must withdraw an RMD based on your age every year from 2026-2034. (You can always withdraw more.). The broker can tell you what it will be. You must withdraw everything and close the account by the end of 2036. If you only withdraw the RMD for 9 years, you will have a big withdrawal in 2036 that could push you into a higher tax bracket or cause other problems, so you might want to space out the withdrawals more evenly by withdrawing more than the minimum amount. You must take the 2026 RMD before 12/31/26 even if you already took the 2025 RMD in 2026. Any withdrawals you make in 2026 will be reported on your 2026 tax return.
