What goes on a W-9
Name, business name (if applicable), federal tax classification (individual, LLC, S-corp, C-corp, etc.), address, and Social Security Number or EIN. The form is signed under penalties of perjury and handed to the payer, who keeps it on file to prepare year-end 1099s. It never gets filed with the IRS, which also means it carries none of the deadlines the 1099 itself does.
Why clients ask for it
They need your tax ID to issue a 1099-NEC (contractor payments) or 1099-MISC (rents, royalties, legal settlements). Refusing or providing a wrong number triggers 24% backup withholding. Established businesses increasingly refuse to release the first payment until the W-9 arrives, which is the correct order of operations on both sides of the table.
The LLC line, where most mistakes happen
A single-member LLC that hasn't elected corporate treatment is disregarded: line 1 carries the owner's name, the LLC's name goes on line 2, and the classification box is 'individual/sole proprietor.' An LLC taxed as an S-corp checks the LLC box with an S. Getting this wrong produces IRS name-TIN mismatch notices (B-notices) for your client and puts your payments on track for backup withholding until it's cleaned up.
If you're the one paying contractors
Collect a completed W-9 from every unincorporated vendor before the first check. Chasing tax IDs in January from contractors who've moved on is an annual small-business ritual with an easy cure. If the IRS sends you a B-notice about a payee's mismatched TIN, you must re-solicit the W-9 and, failing that, start backup withholding; ignoring it moves the liability to you.
When to hesitate before sending one
A W-9 request is routine from someone paying you for services, rent, or interest. It's not routine from strangers, and a completed W-9 contains everything an identity thief wants. Verify who's asking and why, transmit it securely rather than as a plain email attachment, and question requests where no reportable payment relationship exists.
Common questions
- Should I use my SSN or EIN?
- EIN if you have one (and especially if your LLC is taxed as an S-corp or C-corp). SSN if you're a sole proprietor without an EIN.
- Is the W-9 sent to the IRS?
- No. The payer keeps it and uses it to prepare 1099s. The IRS only sees the resulting 1099, which is why accuracy on the W-9 shows up as matching problems later.
- What exactly is backup withholding?
- A flat 24% the payer must skim from your payments and remit to the IRS when your TIN is missing or mismatched. You get it back as withholding credit at filing, but the cash flow hit is immediate.
- Do I need a new W-9 every year?
- No, only when your information changes: new entity, new classification election, new name or address. Payers may re-request periodically as housekeeping.
Related
Personal Income Tax Preparation
Federal and state 1040 preparation with year-round planning. We handle W-2, 1099, K-1, rental, and crypto income for individuals in Florida and all 50 states.
Business Tax Planning
S-corp reasonable salary analysis, entity elections, retirement plan structuring, and Section 179 and bonus depreciation planning for small business owners.
Form 1099-NEC
Businesses issue a 1099-NEC by January 31 for payments of $600 or more to unincorporated contractors. What issuers need from a W-9 and how recipients report it.
Related tax topics
Form 2553 S-Corp Election
Form 2553 elects S-corp tax treatment, due 75 days into the tax year (March 15 for calendar-year businesses). Late election relief covers most misses.
Form 1040-X Amended Return
Form 1040-X corrects income, deductions, credits, filing status, or dependents on a filed return. Refund claims have a three-year window from original filing.
Updating Your W-4
Adjust withholding after marriage, divorce, a new baby, a new job, or a refund or balance over $1,000. The current W-4 uses dollar amounts, not allowances.
Changing Your Address with the IRS
Form 8822 updates your address with the IRS. Undelivered notices don't excuse missed deadlines, so file before a 30-day letter goes to your old address.