The mailing address to file your federal income tax return will vary, based on which state you live in (or if you live outside of the U.S.), and on whether you enclosing a payment or not. Please see the following IRS guide, "Where to File Addresses for Taxpayers and Tax Professionals Filing Form 1040":
https://www.irs.gov/uac/where-to-file-addresses-for-taxpayers-and-tax-professionals-filing-form-1040
