One of my dependents received a w9 form after I already filed. Will this affect my return

[JohnW15 · Accepted solution]

No, this form has nothing to do with the return you filed.    

If someone in your family is asked to fill out a Form W-9 (Request for Taxpayer Identification Number and Certification), it's because the business or person hiring them needs their name, address, and Social Security or tax identification number for payroll and tax reporting purposes.  It's not filed with your tax return, or their either, for that matter.

[tishlicious3]

The W9 was from my dependents health insurance provider not employer,  does your answer still apply

[JohnW15]

Yes, same answer -- the W-9 never needs to be filed with a tax return.