Form W-9 Explained: Request for Taxpayer Identification Number Guide for Small Business
What Form W-9 is, who files it, when it's due, and how to fill it out. Complete guide for small business owners.
Form W-9 is one of the forms every US small business eventually encounters. Here's everything you need to know.
What is Form W-9?
W-9 — Request for Taxpayer Identification Number
Purpose: Request contractor's TIN before paying them
Filing deadline: Before first $600 payment
Who must file Form W-9?
If you're a US-based business or self-employed individual, you likely need to file Form W-9 if any of these apply:
- You're a business paying a contractor $600+
- You request this FROM the contractor before paying them — to collect their TIN
- You don't file W-9 with the IRS; you keep it for your records and use it to generate 1099s
How to complete Form W-9
The form can look intimidating, but the process breaks down into:
1. Collect the information (payee name, TIN, amount paid)
2. Fill out the form (paper or electronically)
3. Deliver copies (to recipient, IRS, and state if required)
4. Keep a copy for your records (7 years recommended)
Penalties for missing Form W-9
Penalties scale with how late you file:
- Up to 30 days late: $60 per form
- 31 days to August 1: $130 per form
- After August 1 or not at all: $330 per form
- Intentional disregard: $660+ per form
For a business with 10 unfiled forms, that's $6,600 in penalties — easily avoided by filing on time.
How TinSuite generates Form W-9
Instead of manually tracking, TinSuite auto-generates Form W-9 at year-end:
- Contractor/employee data auto-populates from your records
- Amounts are pulled from payments/payroll data
- Generated PDF is IRS-ready
- Electronic filing supported