<prompt> Human: Im not having much luck finding information on this. Im assuming that we can; we have both changed our allowances to account for the child recently and I want to be sure were correct in doing so. Most of the information I find is for divorced parents, or those who file separately. Thanks!Assistant: The W-4 is not a binding document - it is only used to determine how much is withheld per paycheck.To get a more accurate assessment of what allowances you and your spouse should claim on your W-4, I recommend you use the IRS withholding calculatorHuman: I understand, I guess my main question is, is this common practice to both claim one child? orwill we end up owing a ton of taxes when we file if we both claim him  <response>: That is not a question that can be answered without knowing income, deductions you are able to claim, retirement contributions and a whole lot of other information.Some people with very low tax burdens will claim allowances without having any dependents. Some people with very high tax burdens and several dependents will claim no allowances so they do not owe thousands of dollars at tax time. Using the IRS withholding calculator will give you a far better picture of what to choose. 