If your boyfriend has signed Form 2848, Power of Attorney, then:
If you paper-file your boyfriend’s return through the mail, simply attach the signed Form 2848 to the complete return.
If you eFile his return, however, the process is a bit more complicated. You'll eFile the return as normal through TurboTax. Then, you'll need to send both the signed Form 2848 and the IRS' Form 8453, U.S. Individual Income Tax Transmittal for an IRS e-file Return to the IRS. On Form 8453, you'll check the second checkbox, for "Form 2848, Power of Attorney and Declaration of Representative." There's no signature requirement on Form 8453. The mailing address for these items is on page 2 of Form 8453.
CAUTION: If you've eFiled your boyfriend’s return, do not include a copy of the return with the Form 2848/8453 package you're sending. It could become detached from the forms you're sending in, the IRS could process it as an original return, and all kinds of problems could ensue.
