1099s: What to Do If a Vendor’s Tax ID Is Missing or Wrong

As year-end approaches, many businesses are preparing 1099 forms for contractors and vendors. But what happens if a vendor’s taxpayer identification number (TIN) — such as a Social Security Number (SSN) or Employer Identification Number (EIN) — is missing or incorrect?

Here’s what you need to know:

1. You’re Still Required to File the 1099

Even if you don’t have a vendor’s correct TIN, you must still file the 1099 with the IRS by the deadline. Leaving it out entirely can create bigger issues.

2. Use the Best Information You Have

• If you don’t have a TIN, file the form with as much accurate information as you can (name, address, payment amount).

• If you know the TIN might be incorrect, file it anyway and make corrections later if necessary.

3. Request a Corrected W-9

• Always request a completed Form W-9 from your vendors before paying them.

• If a vendor refuses to provide one, keep records showing you made the request.

4. Backup Withholding May Apply

If a vendor does not provide a valid TIN, the IRS may require you to withhold 24% of future payments (called backup withholding) and send that amount to the IRS.

5. Keep Documentation

• Save copies of W-9 requests and any communication with the vendor.

• This documentation shows the IRS you made a good-faith effort to comply.

6. Correct Mistakes Quickly

If you later receive the correct TIN or realize an error, file a corrected 1099 with the IRS.

✅ Bottom line: Don’t skip a 1099 because of a missing or incorrect TIN. File what you have, request updated information, and keep good records.

At Hamm Accounting Firm, we help our bookkeeping clients by processing their 1099s to ensure compliance and reduce the stress of year-end filings. Stay tuned for additional updates and guidance as we approach the 2025 1099 season.

Written by Melissa Crowe, Senior Bookkeeper, Hamm Accounting Firm LLLP