If are requesting a refund or
are not enclosing a check or
money order :
Department of the Treasury
Internal Revenue Service
Austin, TX 73301-0002
If you are enclosing a check or money order :
Internal Revenue Service
P.O. Box 1214
Charlotte, NC 28201-1214
https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
page 105
