How do I fill out the W-9? September 07, 2021 03:11 Updated Follow Please fill out line 1 with your legal business name and line 2 with your doing business as name. For further instructions, please visit this link for further instructions (starting on page 2). Related articles Why do I need to fill out a W-9 if my sales are less than $20K? What is the W-9 Form used for? 1099-K Details How often do I have to fill out a W-9? Why does Ritual need me to fill out a W-9 form – I already report my sales from Ritual on my income tax return? Comments 0 comments Article is closed for comments.