Where do I put my apartment number on my form

If you’re referring to the address on your federal income tax return, you enter or edit it like this in TurboTax Online: 

1. Open TurboTax Online
2. Select Tax Home in the left pane
3. On the Hi, let's keep working on your taxes! screen, select the dropdown on the right side of the Personal Info box, then select Continue 
4. On the Personal info summary screen, select Edit to the right of Mailing address
5. On the Enter your current mailing address screen, you can enter your apartment number in the Apt, Ste, Unit box
6. Select Continue

 Don't include "Apartment" in the box.  If you live in apartment 14B, simply enter "14B".

If you’re referring to a different form, provide more information.