Just because you are married doesn't mean you have to file jointly. Some couples find that separately figuring taxes on each spouse's portion of their income and deductions is advantageous. Or they may just feel more comfortable keeping their tax situations separate. Separate filing by married couples, however, can be problematic. Some states view a married couple's income as split 50/50, regardless of which partner earned the money and require that even split to be used even when the spouses file separate returns. Also, many tax breaks and credits are not available when the married filing separately status is used. When one spouse itemizes deductions the other spouse cannot claim the standard deduction, and therefore must itemize to claim their allowable deductions.