Collecting W-9 forms from vendors works best in the fall, before 1099 season. List every payee the client paid by check, ACH or cash for services, skip corporations already on file, and send each one a short request with a deadline. Store returned forms in the client's 1099 folder with the date received, and chase missing ones in early December.
Which vendors need a W-9 form before January?
A vendor needs a W-9 on file when the client may have to send that vendor a 1099. In practice that means individuals, partnerships and LLCs paid for services by check, ACH, wire or cash. The IRS page on Form W-9 describes the form's job: it gives the payer the correct taxpayer identification number to put on an information return.
Start from the payments, not from the vendor list in the accounting system; the method for sorting contractor payments by payment method builds that list from the year's statement lines. The IRS instructions for Forms 1099-MISC and 1099-NEC say card and third party network payments are reported on Form 1099-K instead, so a vendor paid only by card rarely needs chasing.
Ask anyway when the total is close to the reporting amount, which those instructions set at $2,000 of nonemployee compensation for tax years beginning after 2025. A W-9 also tells you the vendor's entity type, and that is often the only way to know whether a payee with "LLC" in its name is taxed as a corporation and can come off the list.
When should W-9 collection start for a client's vendors?
W-9 collection should start before the first payment, and for existing vendors no later than October. A vendor asked in October has weeks to reply. A vendor asked on January 20 is busy with their own year end and may not reply before the 1099 deadline at the end of the month.
The better habit is to make the W-9 part of setting up any new service vendor. The client asks for it with the first invoice, and the bookkeeper does not pay or code the vendor until it arrives. A short note in the client's year-end materials, such as the tax organizer for bookkeeping clients, reminds them which vendors are still missing.
The timing of the books does not change who needs a form. Whether a client keeps its books on cash or accrual, the 1099 list is built from payments actually made, so an invoice accrued in December but paid in January belongs to next year's list. The differences between the two methods are covered in cash vs accrual for small business taxes.
A W-9 request email to send vendors
A good W-9 request is short, names the client, says why the form is needed and gives a date. Vendors ignore long letters and vague asks. Send it from the client's address when possible, since the vendor knows the client, not the bookkeeper.
The template below is an example. Replace the bracketed parts.
Subject: W-9 needed by [date] for [Client business name]
Hi [Vendor name],
Thank you for your work for [Client business name] this year. To prepare year-end tax forms, we need a completed Form W-9 from you. You can download the current form from the IRS website, fill it in and reply to this email with the signed copy, or upload it at [secure link].
Please send it by [date]. If you have already sent one this year, no action is needed.
Thank you, [Name], on behalf of [Client business name]
Ask vendors to use a secure upload link rather than plain email when one is available, because the form carries a Social Security or employer identification number.
Track each request in a simple table so nobody is chased twice or forgotten. An example:
| Vendor (example) | Requested | Followed up | Received | Entity type |
|---|---|---|---|---|
| Rivera Photography | Oct 6 | Oct 27 | Oct 30 | Sole proprietor |
| Blue Fern Copywriting LLC | Oct 6 | Oct 9 | S corporation | |
| Metro Office Cleaning | Oct 6 | Oct 27, Nov 17 |
Storing W-9 forms in each client's 1099 file
Each client needs one folder for W-9 forms, kept with that client's tax-year records and closed to anyone who does not work on the account. Name each file with the vendor and the date received. A W-9 holds a taxpayer ID, so treat it like any other document with sensitive personal data.
Three habits keep the folder useful:
- One current form per vendor. When a vendor sends a new W-9 because their name or entity changed, keep both, and note which is current.
- A summary list. Record vendor, entity type, whether the ID was provided and the date received. The 1099 preparer works from the list and opens the form only when needed.
- A yearly check. Before October, scan the list for vendors who changed names or structure during the year.
If you are setting up these processes for your first clients, add the W-9 folder to the standard file structure from day one. The ideas in landing your first bookkeeping client work better when the onboarding checklist already includes it.
Vendors who never return a W-9
Some vendors never return a W-9, even after two reminders. Record every request and follow-up with its date, tell the client which vendors are still missing, and let the client and preparer decide the next step. The record of requests matters if the IRS later questions a missing ID.
The rules give the payer a lever. The IRS page on backup withholding explains that a payer may be required to withhold 24 percent from future payments when the payee fails to provide a correct taxpayer identification number. Telling a slow vendor that future payments may be reduced until the form arrives often gets a reply within days. Whether and when to start withholding is the client's decision, made with the preparer.
Finding which payees need forms is easier when the year's statements are already converted and grouped by payee. AutoBankConvert turns each client's statement PDFs into categorized lines, so the vendor list for W-9 requests comes from real payments.