Can I do someone else’s taxes from my app?

You appear to be using TTax On-Line --NOT the downloaded desktop version that is installed on YOUR computer.

If you are using the On-Line version, one of the features is that the  user ID/account can be used for ONE and only one tax return --e-filed or printed/mailed.  (Has always been this way)

If you need (or try) to prepare more than one return you MUST create a new user ID/account and pay for EACH return  --if you want to use the on-line version.  The same e-mail address can be used for multiple DIFFERENT account ID's.

If you try to prepare a second return using the same ID you will overwrite all data for the first return
and it will be lost forever; thus if the IRS challenges your first return you will no longer have a basis
to respond to questions.

Starting another return (with the Online version)
https://ttlc.intuit.com/questions/1894512-how-do-i-start-a-second-return-in-turbotax-online


If you are using the Desktop version (which you install on your own computer) simply open/launch the program and select the BLUE "Start a New Return" button (or select "New Return" under the "File" tab in the menu bar) near the center of the window; TTax should then save each return with a unique filename based on the first name listed on the actual return.  Multiple returns are no problem and no additional cost. The IRS limits you to 5 e-filed returns; however you can print and mail additional returns. 

If you use TurboTax online, you'll need to create another TurboTax to file for someone else.

Please read the instructions in this TurboTax Help topic.

If you use TurboTax CD/Download, you can prepare an unlimited number of returns and e-file up to 5 federal returns.

Please read this TurboTax Help topic.

I need help doing my taxtes