IRS TIN matching is a free pre-filing service that lets payers check payee name and Taxpayer Identification Number combinations against IRS records before submitting Forms 1099 and similar information returns. Running these checks catches errors that would otherwise trigger CP2100 notices, force 24% backup withholding on future payments, and generate penalties that start at $60 per return and climb from there.
What the TIN Matching Program Does
The program compares a name and TIN you submit against IRS records and returns one of three results: match, no-match, or error.1Internal Revenue Service. Taxpayer Identification Number (TIN) Matching Tools It is a verification tool, not a correction service. You use it before filing to catch problems, not after filing to fix them.2Internal Revenue Service. Taxpayer Identification Number (TIN) Matching
Access is limited to payers who submit information returns and their authorized agents. You reach the service through the IRS e-Services portal, which is separate from the FIRE system used to actually file returns electronically.3Internal Revenue Service. Publication 2108 – Federal Agency TIN Matching Program
Registering for e-Services
To use TIN Matching, you need an IRS e-Services account verified through ID.me. Setup requires a government-issued photo ID such as a driver’s license, state ID, or passport, along with your own SSN or ITIN and multifactor authentication through an authenticator app or phone-based verification. Identity verification is a one-time step.4Internal Revenue Service. Creating an Account for IRS.gov
Interactive and Bulk Matching
Once inside, you have two ways to submit name/TIN combinations.1Internal Revenue Service. Taxpayer Identification Number (TIN) Matching Tools
- Interactive TIN Matching checks up to 25 combinations at a time and returns results immediately. You can submit up to 999 requests in any 24-hour period.
- Bulk TIN Matching accepts an uploaded file of up to 100,000 combinations. Results come back within 24 hours.
Interactive matching fits vendor onboarding, when you want to verify a new payee’s information the moment you receive it. Bulk matching fits year-end cleanup: run your full payee roster through the system before January and correct problems while there is still time to redo a W-9.
Getting the Data You’ll Check
Before you can match anything, you need the payee’s information on file. Federal law requires anyone filing a return about another person to request and include that person’s identifying number, and the standard way to do this is by sending IRS Form W-9, Request for Taxpayer Identification Number and Certification.5Office of the Law Revision Counsel. 26 US Code 6109 – Identifying Numbers The payee provides their legal name (or business name), their TIN, and a signed certification. You keep the W-9 in your files; it does not go to the IRS.
The Sole Proprietor Trap
One error causes an outsized share of mismatches. A sole proprietor must enter their individual name on the W-9’s “Name” line, not just their business name. The business or “doing business as” name goes on the separate business name line. For the TIN, a sole proprietor can enter either their SSN or their EIN, though the IRS encourages using the SSN. Getting this pairing wrong is the fastest way to generate a no-match result.
What Happens if You Skip Matching
File a return with a missing or incorrect TIN and the IRS sends a CP2100 or CP2100A notice listing every payee with a problem, whether the TIN was missing, obviously invalid, or simply didn’t match records.6Internal Revenue Service. Understanding Your CP2100 or CP2100A Notice The notice starts a series of obligations that grow more burdensome with each cycle.
First B-Notice
The first time a payee appears on a CP2100 or CP2100A notice, you must send them a “First B-Notice” along with a blank Form W-9. The payee corrects their information and returns a signed W-9.7Internal Revenue Service. Backup Withholding “B” Program If they don’t respond, you must begin backup withholding on all future payments to that payee no later than 30 business days after you received the CP2100 or CP2100A notice.6Internal Revenue Service. Understanding Your CP2100 or CP2100A Notice
Second B-Notice
If the same payee appears on a CP2100 or CP2100A notice again within three years, you send a “Second B-Notice.” A fresh W-9 is no longer enough. The payee must provide a copy of their Social Security card (for SSN holders) or an IRS Letter 147C confirming their name and EIN.7Internal Revenue Service. Backup Withholding “B” Program Backup withholding continues until they hand over that documentation.
When the payee finally provides a valid TIN, you must stop backup withholding within 30 calendar days of receiving it.6Internal Revenue Service. Understanding Your CP2100 or CP2100A Notice
The Withholding Rate
Backup withholding is 24% of every reportable payment to the affected payee, set as the fourth lowest rate under the individual income tax brackets.8Office of the Law Revision Counsel. 26 US Code 3406 – Backup Withholding You deposit the withheld tax electronically through EFTPS and report it annually on Form 945.9Internal Revenue Service. Instructions for Form 945
Penalty Amounts for Bad TINs
Filing an information return with a wrong or missing TIN is a failure to file a correct return under IRC Section 6721. Penalties are per return and scale with how quickly you fix the problem. For returns due in 2026:10Internal Revenue Service. 20.1.7 Information Return Penalties
- Corrected within 30 days of the due date: $60 per return, capped at $683,000 per year.
- Corrected after 30 days but by August 1: $130 per return, capped at $2,049,000 per year.
- Corrected after August 1 or never corrected: $340 per return, capped at $4,098,500 per year.
- Intentional disregard: $680 per return with no annual cap.
Small businesses with average annual gross receipts of $5 million or less get lower annual caps: $239,000 for corrections within 30 days, $683,000 for corrections by August 1, and $1,366,000 for later corrections.10Internal Revenue Service. 20.1.7 Information Return Penalties The per-return amounts don’t change with business size.
The math becomes uncomfortable quickly. A payer filing 500 returns with uncorrected TIN errors past August 1 is looking at $170,000 in exposure. That single number is usually enough to make the case for running bulk TIN matching before filing.
Reasonable Cause and Why Matching Still Matters After the Fact
The IRS can waive penalties for incorrect information returns if you show reasonable cause and demonstrate you were not willfully negligent. The regulation lays out two paths: significant mitigating factors such as an established history of compliance, or events beyond your control. Either way, you must show you acted responsibly before and after the error.11eCFR. 26 CFR 301.6724-1 – Reasonable Cause
Documented use of the TIN Matching Program is among the strongest pieces of evidence for that defense. It shows a concrete verification step rather than a hope-and-file approach. Paired with records of W-9 solicitation and prompt responses to CP2100 notices, it forms a defensible pattern. Reasonable cause is never automatic, but a filer who can produce matching logs starts from a much better position than one who cannot.