W-9: Request for Taxpayer Identification Number and Certification

Form W-9 is used in the U.S. income tax system by a third party who must file an information return with the IRS. It requests the taxpayer identification number of the taxpayer. The form is never actually sent to the IRS, but is maintained on file for verification purposes.

Internationals will be asked to sign a W-9 in the year they become resident aliens for tax purposes. (Before that, the W-8BEN is signed.)

Purposes of the W-9:

• Obtain a taxpayer identification number
• Certificate of US status
• Claim exemption from withholding under a treaty for a resident alien
• The W-9 replaces the Form 1078 that was used for a foreign national to declare US tax residency status to a payer.

Treat the individual for withholding and reporting purposes in the same manner as a U.S. citizen.

If you are making a payment to a foreign national who would be taxed at 30% if the individual were a nonresident alien, you should have the signed From W-9 for audit purposes.

Note that the IRS now requires treaty claims for exemptions from withholding of resident aliens to be made on Form W-9.