Get your taxes done using TurboTax

Go back to the personal information/My Info section and click on Revisit/Edit next to your name.   On the About your household screen, under you marital status, change your answer to Plan to file separately or as Head of Household (special rules apply).   

Go through the rest of the personal information questions.   If you have a qualifying person entered, TurboTax will choose the Head of Household status for you if you meet the requirements.  

Even if you were legally married as of December 31, you're considered unmarried (and therefore eligible for Head of Household) if all five of these conditions apply:

1. You won't be filing jointly with your spouse.
2. Your spouse didn't live in your home after June (temporary absences due to illness, school, vacation, business, or military service don't count).
3. Your home was your child's, stepchild's, or foster child's main home for more than half the year (non-child dependents in your home don't qualify).
4. You paid more than half the costs of keeping up your home during the tax year.
5. You meet the qualifications to claim the child as your dependent, even if the other (noncustodial) parent is actually claiming the child as a dependent on their return.   @vsearle48