For US Merchants:
The W-9 form is used for an individual or entity (Form W-9 requester - MoreCommerce) who is required to file an information return with the IRS. The requester must obtain your correct taxpayer identification number (TIN) which may be your social security number. (SSN), individual taxpayer identification number (ITIN), adoption taxpayer identification number (ATIN), or employer identification number (EIN), to report on an information return the amount paid to you, or other amounts reportable on an information return, in this case, Form 1099.
https://www.irs.gov/pub/irs-pdf/fw9.pdf
For NON-US Merchants:
The W-8BEN-E form is used for reporting to the IRS information about a non-U.S. company earning money from U.S. employers
https://www.irs.gov/pub/irs-pdf/fw8bene.pdf
The W-8BEN form is used for reporting to the IRS information about a non-U.S. individual earning money from U.S. employers
https://www.irs.gov/pub/irs-pdf/fw8ben.pdf
Once you have completed the applicable tax form, please email it to tax-forms@help.morecommerce.com and we will make sure it is filed accordingly.