It depends on the type of annuity and whether the decedent had been drawing on the account before their death.
The annuity starting date is the later of the first day of the first period for which you received a payment or the date the plan's obligations became fixed.
If the original owner of the account has been drawing on it prior to death, the annuity starting date will be the first day of the month in which those payments began.
You may need to contact the agency or company issuing the annuity to determine the starting date.
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