No.The purpose of a W-9 Form is simply a request for your taxpayer identification number.The form in and of itself does not affect your income.However, if a company is asking for it, that means they are about to pay you (a US citizen or resident alien) as an independent contractor.The sum of the those payments will result in a 1099 Form, which will be given to both you and reported to the IRS shortly after December 31st.Examples of 1099 Forms include (but are not limited to):u2022 Form 1099-INT (interest earned or paid)u2022 Form 1099-DIV (dividends, including those from stocks or mutual funds)u2022 Form 1099-MISC (various types of income, prizes, awards, or gross proceeds)u2022 Form 1099-B (stock or mutual fund sales and certain other transactions by brokers)u2022 Form 1099-S (proceeds from real estate transactions)u2022 Form 1099-K (merchant card and third party network transactions)u2022 Form 1098 (home mortgage interest), 1098-E (student loan interest), 1098-T (tuition)u2022 Form 1099-C (canceled debt)u2022 Form 1099-A (acquisition or abandonment of secured property)The IRS will expect you to pay income taxes based upon what has been reported to them. If you live in a state that collects income taxes, so will they.