Anuity start date.

[Alexisn119]

When asked to enter anuity start date is for the current calander year or from the time you first retired?

[leeloo]

The annuity start date is the very first time you had a distribution. 

The "plan cost at annuity start date" refers to your total after-tax contributions in the plan, if you made any. If you did not make any after-tax contributions into these accounts, enter "0" (zero) in the plan cost entry.

[TomK2023]

Your annuity start date is the date when you started receiving your first check (your distributions).