The information on line 1 of the W9 must match the information used on your federal tax return as associated with your EIN (Employer Identification Number or Social Security Number).
The name on line 1 must match the name associated with the EIN or Social Security Number listed in Part I of form W9.
Because the majority of questions about the W9 came from individuals who are sole proprietors, I included the following from the IRS.gov website:
The IRS defines a sole proprietor as “someone who owns an unincorporated business by himself or herself.”
Completing a Schedule C with your 1040 tax form showing that you have business activity is about the only thing that shows that you are a sole proprietor to the IRS.
The following would make a W9 incomplete:
Name in Line 1 does not match the EIN or Social Security Number in Part 1;
Federal Tax classification in Line 3 does not match the EIN or Social Security Number in Part 1 of the W9 form and failure to select a classification if LLC selected;
Address, City, State, Zip in Line 4 and Line 5 are not filled out;
Certification: A W9 form that is not certified in Part II with a signature of a U.S. person.
