What you’ll need to file Form 8849

-Name and address. Make sure it is accurate and matches what the IRS has on file.
-P.O. Box. If your post office does not deliver mail to
your street address, show your P.O. box number instead. If you have a
foreign address, enter the information in the following order: city,
state or province, country, then the postal code.
-Taxpayer Identification Number. Enter your Employer Identification
Number. If you are not required to have an EIN, enter your social
security number. An incorrect or missing number will delay processing of
your claim.