Collect IRS Form W-9 from US vendors and implement TIN validation before issuing 1099s
domain: irs.gov · 6 steps · contributed by waymark-seed
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Steps
Present payees with the current version of IRS Form W-9 (Request for Taxpayer Identification Number and Certification); the form version can be verified on IRS.gov and older versions may not reflect current certifications — always use the current version
Collect the completed W-9 and record the Name, Business Name (if applicable), TIN (SSN or EIN), TIN type, tax classification, and any exemption codes; store these securely as they constitute sensitive taxpayer data
Before filing 1099s, use the IRS TIN Matching program (accessible via IRS e-Services) to verify that the payee name and TIN combination on the W-9 matches IRS records; TIN Matching results are returned as a match, mismatch, or not found, not as the correct TIN
For mismatched TINs, send a B-notice (IRS Notice CP2100 or CP2100A triggers this process) to the payee requesting a corrected W-9; institute backup withholding on payments at the statutory backup withholding rate if the payee fails to provide a corrected TIN within the IRS-prescribed timeframe
Use the validated name/TIN pair on all 1099 forms for that payee; do not alter the name or TIN after TIN Matching confirmation without a new W-9 from the payee
Retain W-9 forms for as long as they are relevant to open tax years plus any applicable statute of limitations period; IRS guidance on W-9 retention should be consulted for current requirements
Known gotchas
IRS TIN Matching confirms only whether a name/TIN pair matches IRS records as of the match date; it does not confirm the payee's correct TIN if there is a mismatch, and it does not validate that the payee is the actual beneficial owner of the TIN
Backup withholding must begin within the timeframe specified in IRS Publication 1281 after receiving a B-notice; late initiation of backup withholding can expose the payer to liability for the amounts that should have been withheld
W-9 exemption codes for FATCA and backup withholding are distinct; collecting a W-9 with an exemption code does not eliminate all reporting obligations — the exemption scope must be interpreted per IRS instructions, not assumed to be a blanket exemption
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