You enter box 23 ( Number of Months - Retirement) on a T4A(P) slip.
This is how you can do this using TurboTax Online:
1. Click on Find at the top right-hand corner, type "T4A", select "T4A(P) Canada Pension Plan Benefits" from the list, and click Go.
2. In the T4A(P) Summary click on "Edit" beside the slip.
3. There you will find box 23 in the top row.
4. Enter the amount for "No. of Months - Retirement" (Box 23).
5. Then click on Done with T4A(P) to save your information and again on the next screen Done with T4A(P).
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