Filing status can change whenever your life changes. No matter how you filed your taxes last year, you can change it now if you qualify for a different status. If you have the option to file more than one way -- married but separate or head of household, for instance -- you can pick whichever one gets you the best tax deal.
Head of Household
You cannot switch filing status mid-year. For the IRS, what matters is December 31: if you're divorced on the last day of the year, say, you're unmarried for the whole year. To qualify as head of household, you must either be unmarried, or in the eyes of the IRS, "considered unmarried" at the end of the year. You must also pay more than half the cost of running your household, and have a qualifying person live with you more than six months of the year.
If you've never been married or you divorced during the year, you're obviously unmarried. Even if you're married, however, the IRS can consider you unmarried if your spouse didn't live with you for the last six months of the year. It doesn't count if she's away because she's stationed overseas, attending college or working in another state -- it only applies if you've split up. You must file separate returns -- head of household doesn't work with a joint return.
To be eligible to file as head of household, you must have a dependent: either a qualifying child who pays for less than half his own support -- it doesn't matter who pays the rest -- or a qualifying relative who gets at least half his support from you and lives with you more than half the year. The IRS allows lots of exceptions. For example, a child who makes his home with you but spends most of the year at boarding school, or a parent whom you support but who doesn't live with you could both qualify. IRS Publication 501 details the web of rules.
Filing as a head of household doesn't give you as good a deal as a joint return, but it beats separate returns or filing as a single. For the 2013 tax year, for instance, you get an $8,950 personal deduction as head of household, compared to $12,200 as married filing jointly and $6,100 for married filing separately. Your tax rates are better than if you filed a single return, and you can qualify for many tax credits denied the married-but-separate filer.
A graduate of Oberlin College, Fraser Sherman began writing in 1981. Since then he's researched and written newspaper and magazine stories on city government, court cases, business, real estate and finance, the uses of new technologies and film history. Sherman has worked for more than a decade as a newspaper reporter, and his magazine articles have been published in "Newsweek," "Air & Space," "Backpacker" and "Boys' Life." Sherman is also the author of three film reference books, with a fourth currently under way.