Prevent TIN/name problems before filing—and know what to do if a notice arrives.
Use local pre-filing checks, understand CP2100 and CP2100A notices, follow First and Second B Notice workflows, and learn when the official IRS TIN Matching program may help.
✓ Local cleanup tool does not send your file anywhereSix tools for TIN/name cleanup and notice response
Pre-Filing TIN Cleanup
Scan a CSV locally for missing, malformed, scientific-notation, whitespace, and inconsistent TIN/name values.
Check a CSV →CP2100 / CP2100A Helper
Choose what the notice says and whether this is the first or second notice to see the response path to review.
Open helper →B Notice Workflow
Review First and Second B Notice timing, W-9 handling, documentation, and withholding checkpoints.
Review workflow →Backup Withholding Guide
Understand when backup withholding can begin, the current 24% rate, and Form 945 reporting basics.
Read guide →IRS TIN Matching Guide
Learn who can use the official IRS service, which forms are currently listed as eligible, and interactive vs. bulk matching.
TIN Matching guide →Form-Specific TIN Guides
Open a TIN/name mismatch guide for 1099-NEC, 1099-K, 1099-INT, W-2G, and other common notice forms.
Choose a form →TIN/name mismatch guides by information return
These guides connect the notice workflow to the exact TIN/name fields in the bundled CSV template.
Formatting checks are not IRS TIN Matching.
The local checker can find malformed or missing TIN values and inconsistent names in your own CSV. It cannot query IRS records or tell you whether a name/TIN combination matches the IRS database. For eligible payers and forms, use the official IRS TIN Matching service for that purpose.
IRS sources: TIN Matching · Backup Withholding B Program · Publication 1281
Questions about TIN cleanup and CP2100 notices
What is a CP2100 or CP2100A notice?
It is an IRS notice telling a payer that one or more payee taxpayer identification numbers are missing, obviously incorrect, not currently issued, or do not match IRS records. The two notices contain the same type of information; the IRS says CP2100 is used when 50 or more information returns have errors and CP2100A when fewer than 50 have errors.
Can 1099ERICH verify a name and TIN against IRS records?
No. The free cleanup checker and 1099ERICH can identify local formatting and data-quality risks, but only the IRS TIN Matching service can return an IRS match result for eligible payers and forms.
What is a First B Notice?
For an incorrect name/TIN combination that agrees with the payer records, Publication 1281 describes a First B Notice process that includes sending the notice and Form W-9 to the payee within the required time.
What changes after a second incorrect-TIN notice within three years?
The IRS uses a Second B Notice process. The payer does not send Form W-9 with the second notice; the payee generally must obtain prescribed validation such as an SSA Social Security card or IRS Letter 147C, depending on the TIN type.
What is the current backup withholding rate?
The IRS currently states that backup withholding is 24% when the backup-withholding rules apply. Whether withholding is required depends on the specific reason and timing, so review the current IRS instructions and Publication 1281.
Move from a free check to the complete 1099ERICH workflow.
The free tools help diagnose individual filing problems. 1099ERICH is the $299 Windows desktop workflow for importing CSV or Excel data, validating records, printing recipient copies, and creating IRIS-ready CSV files.