Compare the listing(s) with your records. For missing TINs: If you have not started backup withholding, begin to do so immediately and continue until you receive a TIN. You must make up to three solicitations for the TIN (initial, first annual, second annual) to avoid a penalty for failing to include a TIN on the information return.
For incorrect TINs: Compare the accounts on the listing with your business records. Follow the specific solicitation requirements in order to avoid a penalty for failure to include the correct TIN on an Information Return. If they agree, send the appropriate “B” Notice to the payee. If an account does not agree, this could be the result of a recent update to SSA records, an error in the information you submitted, or an IRS processing error. If this type of error occurred, the only thing you should do is correct or update your records, if necessary. Remember: You do not have to call or write to the IRS to say that you made the correction or update to your records.
For additional information see Publication 1281, Backup Withholding.