W-9 collection means getting a completed Form W-9 from every vendor a client pays before the first payment, then keeping it current. Request it at vendor setup, log it in a tracker with the legal name, entity type, TIN type and form revision, and ask for a new one whenever the vendor's name or entity changes.
What is a W-9 form, and who signs it?
A W-9 form is the IRS form a U.S. person uses to give a payer its correct taxpayer identification number (TIN). The payee, meaning the vendor or contractor being paid, fills it in and hands it to the payer. The payer keeps it on file and uses it to prepare information returns such as Form 1099-NEC.
The current version is the March 2024 revision, according to the IRS About Form W-9 page. The form's own header says to give it to the requester and not to send it to the IRS. For a bookkeeping firm, that means the client's file, not the IRS, is where the form lives.
The Instructions for the Requester of Form W-9 define the two roles. A requester is anyone required to file an information return. A payee is anyone required to give the requester a TIN. When a firm collects W-9s for a client, the client is the requester and each vendor is a payee.
The Form W-9 (Rev. March 2024) asks for:
- Line 1, the name of the entity or individual, which must match the name on its tax return.
- Line 2, a business, trade or "doing business as" name, or a disregarded entity's name.
- Line 3a, one federal tax classification box, such as individual or sole proprietor, C corporation, S corporation, partnership, trust or estate, or LLC with its tax classification letter.
- Line 4, any exempt payee code or FATCA exemption code.
- Part I, the TIN, as either a social security number or an employer identification number.
Part II is the certification. Under penalties of perjury, the signer certifies that the TIN is correct, that the payee is not subject to backup withholding, that the payee is a U.S. person, and that any FATCA code entered is correct.
Whether that signature is required depends on the payment. The form's Part II instructions say that for "other payments", which include payments to a nonemployee for services, the payee must give a correct TIN but does not have to sign the certification unless it was previously told it gave an incorrect TIN. Interest, dividend and broker accounts opened after 1983 need a signature. Many firms ask every vendor to sign anyway, so one policy covers every case.
A W-9 collection workflow for bookkeeping clients
A W-9 collection workflow is the routine a firm runs for each bookkeeping client so that every vendor has a form on file before year-end. It has three steps: request the W-9 when a new vendor is set up, track each request until a usable form comes back, and file the returned form where the 1099 preparer can find it.
Request at onboarding
The cheapest moment to get a W-9 is before the client pays the vendor for the first time. At that point the vendor wants to be paid, and the request is part of normal setup. Ask the client to send each new vendor's W-9 with the first invoice, or to forward the vendor's contact so the firm can request it.
Add the request to the firm's intake routine for new clients too. A client who joins mid-year may have paid contractors for months with no forms on file. The client onboarding checklist for accounting firms covers where a vendor list request fits in the first week.
Track every request
Track W-9s in one sheet per client, one row per vendor. A request is open until a form arrives that passes review, not just until a file arrives. The example below shows the columns.
| Vendor | Legal name (line 1) | Business name (line 2) | Entity type (line 3a) | TIN type | Signature date | Form revision | Status |
|---|---|---|---|---|---|---|---|
| Example vendor A | Marisol Ortega | Ortega Tile & Stone | Individual/sole proprietor | SSN, XXX-XX-4821 | 2026-03-04 | Rev. March 2024 | On file |
| Example vendor B | Brightfield Cleaning LLC | LLC, P | EIN, XX-XXX3307 | Rev. March 2024 | Unsigned, signature requested | ||
| Example vendor C | Northline Data Services Inc. | C corporation | EIN, XX-XXX5512 | 2023-08-19 | Older revision | Old revision, new form requested | |
| Example vendor D | Harbor Sign Co. | Requested 2026-09-02 |
All names, dates and masked numbers above are fictional. Keep only the last four digits of a TIN in a tracker that many people can open, and keep the full form in the client's document file.
The status column does the work. Useful values are requested, received, on file, needs correction and not required. "Not required" closes a row for a vendor the client will never pay again, with a note saying why.
File the returned form
File each W-9 under the client and vendor, and record the date it came in. When January arrives, the 1099 preparer should be able to open the tracker, filter for "on file" and start. Vendors still marked "requested" become the year-end chase list, which the post on building the 1099 vendor list from the general ledger picks up from the ledger side.
W9 OCR: reading name, entity type and TIN off returned forms
W9 OCR is optical character recognition applied to returned W-9s: software reads the printed or handwritten fields and turns them into tracker rows. It saves typing, but the W-9 has a few fields OCR reads poorly, so each extracted row needs a human glance before it is marked on file.
The fields worth capturing are line 1, line 2, the line 3a box and LLC letter, line 4 codes, the TIN and which of the two Part I boxes it sits in, the signature date, and the revision printed in the top left corner. The revision matters because the March 2024 form added line 3b, according to the Form W-9 (Rev. March 2024), so an older form has a different layout.
Fields OCR tends to confuse:
- Line 1 and line 2. A sole proprietor who writes the business name on line 1 creates a mismatch the reader cannot detect. The W-9 instructions say a sole proprietor must enter the individual name on line 1 and the business name on line 2.
- Checkboxes. A faint tick, a circled box or two ticked boxes on line 3a can read as the wrong classification or none.
- The LLC letter. A handwritten "C", "S" or "P" beside the LLC box is easy to misread.
- Which TIN box. Nine digits in the SSN boxes and nine digits in the EIN boxes are different facts about the payee.
- Handwritten digits. A 1 read as a 7, or a 5 read as a 6, gives a TIN that looks fine and is wrong.
Format problems can be caught at extraction time. A TIN with eight digits, a letter, or an impossible prefix is wrong before anyone asks the IRS. The post on what a TIN format check catches on a W-9 lists the patterns, and the wider post on W-9 TIN matching explains how that differs from the IRS program.
Schema CPA reads returned W-9s as part of a client's file and runs a TIN pattern check on each one, which flags a malformed number. It does not confirm the name and number with the IRS. The list of document categories shows where W-9s fit among the forms it reads.
How often should W-9 collection be repeated?
W-9 collection should be repeated whenever the information on file stops being true, not on a fixed calendar. The common triggers are a change of legal name, a change of entity type, a new TIN, and a vendor who claimed an exemption that no longer applies. An old form revision is a softer trigger that many firms also use.
The Form W-9 (Rev. March 2024) puts the duty on the payee under "Updating Your Information". A payee must give updated information to anyone it told it was an exempt payee if it no longer is. The form's examples include a C corporation that elects to be an S corporation and an organization that is no longer tax exempt. It also says a payee must furnish a new W-9 if the name or TIN changes for the account.
In practice, vendors rarely volunteer the update. Watch for signs in the client's books:
- An invoice arrives under a new business name or with "LLC" or "Inc." added.
- A payment bounces back with a note about a new legal entity.
- A sole proprietor starts invoicing from a corporation.
- The client's bank shows payments to a new payee name for the same work.
Each of these is a reason to request a fresh W-9 and update the tracker row.
Form revisions are a policy choice. The IRS About Form W-9 page names March 2024 as the current revision, and the form describes what changed on lines 3a and 3b, but neither says an older signed form stops being valid. Some firms ask for the current revision whenever a vendor sends a new form anyway, so the file uses one layout.
A vendor that never sends a form at all is a separate problem with its own consequence. The post on when backup withholding starts for a missing W-9 covers what the payer must do when the TIN never arrives.
W-9 collection mistakes: unsigned forms, wrong names and old revisions
W-9 collection mistakes are the errors that leave a firm holding a form it cannot rely on. Three cause most of the trouble: a missing signature where one is required, a line 1 name that does not match the TIN, and a form so old the vendor's facts have changed. Each tends to surface in January.
Unsigned forms
An unsigned W-9 is not always a defect. The Part II instructions on the Form W-9 (Rev. March 2024) say a payee receiving "other payments", such as nonemployee pay, must give a correct TIN but need not sign unless it was previously told its TIN was incorrect. The problem is the cases where a signature is required. IRS Publication 1281 says that after a first "B" notice, the payer needs a TIN the payee certifies as correct on Form W-9 to stop or prevent backup withholding. A firm that accepted an unsigned form for a vendor in that position has nothing usable on file.
Wrong names
A line 1 name that does not match the TIN is the most common reason a W-9 fails later. Publication 1281 explains that a sole proprietor must always give the individual name on the first name line, and may add a business name on the second. It also says a business EIN must be used for a partnership, corporation or LLC that is not disregarded. "Ortega Tile & Stone" on line 1 with an SSN in Part I looks complete and will not match.
Old revisions
An old revision is a mistake mostly because of what it implies. A form signed in 2018 says nothing about whether the vendor changed entity type since. Check the date and the revision code together, and ask for a new form when a vendor's invoices suggest the facts have moved.
Accepting the client's word
The last mistake is marking a vendor complete because the client says "we have that one". Ask for the form itself. A W-9 that cannot be produced in January does not help the 1099 preparer, and the year-end 1099 vendor W-9 collection process is much shorter when the tracker holds real forms.