Be sure to check the 'multiple jobs' box on the w form. And read the instructions on filling it out.How do I fill out W4 with three jobs? This video goes over how to complete Form W-4 if you have 2 jobs or if you are married and your spouse works as well. The IRS instructions for the W4 includes the line: Multiple jobs. Complete Steps 3 through 4(b) on only one Form W-4. Read the following instructions carefully before completing this application. Please complete the application on a computer or print in ink. If you have a working spouse or more than one job, it is best to check the box "SINGLE or MARRIED (with two or more incomes). Apply to Administrative Associate, Medical Receptionist, Front Desk Agent and more!