Editor’s Picks Tax Guide What is a W-3 Form and How to Fill It Out Online? The Form W-3, along with W-2, is sent to the Social Security Administration (SSA) on an annual basis. The purpose is to show the total earnings for all W-2 ... Tax Guide Employers’ Guide to W-3 As an employer, you know you need to fill out and submit W-2 forms so the IRS can keep track of your employees’ total earning, medicare wages, Social Security ...