W-9 Form (Request for Taxpayer Identification Number and Certification)

The W-9 Form (Request for Taxpayer Identification Number and Certification) is an IRS form used to request the taxpayer identification number (TIN) of a U.S. person (including resident alien) and to request certain certifications and claims for exemption. A substitute W-9 may be developed and used if its content is substantially similar to the official IRS Form W-9 and it satisfies certain certification requirements.