To pay the amount you owe, you have the following options:
- You can include a check made payable to the "UNITED STATES TREASURY" and write at the back of the check your Social Security Number or Individual Tax Identification Number (SSN or ITIN) along with your full name. After that, you should send your check along with your Federal tax return without stapling it;
- You can pay via money order;
- You can also pay the balance due online through the following site https://www.irs.gov/payments If you are paying via Credit/Debit Card, you should write the Confirmation number you'd receive and the amount you owe on the upper left corner of the 1040-NR form (page 1).
N.B Please do NOT include the commission fee you were charged when writing the amount you owe on your tax return.