You can enter your OAS and GIS on the T4A (OAS) (Old Age Security) page. You can enter you CPP on the T4A (P) (Canada Pension Plan or Quebec Pension Plan benefits) page. If you are using TurboTax Online or the EasyStep mode of TurboTax CD/Download, you can use the Find tool (magnifying glass) to search for those pages. Type “t-slips” into the search bar and then select “T-slips” from the list. Then you can check off the T4A (OAS) & T4A (P) from the list and click “Continue”.
If you are using Forms mode of TurboTax CD/Download, you can click “Forms” on the blue icon bar to search for the T4A (OAS) & T4A (P).