<prompt> Human: Do my girlfriends social security and alimony from her previous marriage count as taxable wages that I would have to account for on line B of the W-4 form or can I just file as being single with one job? We arent married yet, but Im the only one actually working. If this question has been fielded in the FAQ, then I apologize if I missed it.  <response>: No. You do not claim income from anyone else on your taxes except a spouse and then only if you are married filing jointly.As for the W4, you can put anything you want on there. If you have high itemized deductions, you reduce your withholding by claiming more exemptions, not on the actual tax return, just on the W4. If you have outside income like investments, NOT like a girlfriend, unless you plan to be married before the end of the year then you would claim less exemptions so you dont end up owing so much tax you get a penalty. 