Obtain Form W-9. In general, Form W-9 should be provided by the business or organization that asks you to complete it. If not provided, Form W-9 is available from the IRS website or by phone at 1-800-829-3676.
Complete the information header, providing information about yourself or your business. This includes your name (as known to the IRS), your formal business name (if applicable), an indication if you are completing the form as an individual income tax payer or a business entity, and your address. The address should match the address on file with the IRS. If you are filing Form W-9 on behalf of your business, this should be your business address.
Put your Taxpayer Identification Number in Part I. Your TIN is either your social security number if you are filing this form as an individual income taxpayer or your employer identification number if you are filing this form on behalf of your business. The SSN or EIN should match the IRS' records for the name and address you previously provided.
Sign Form W-9 in Part II of the form. Here you certify that the information you have provided is correct and that the IRS has not notified you that you are subject to backup withholding.
Return the completed form to the business or organization that requested it. You do not need to send the form to the IRS.