Can I file as Head of Household (HOH) if sharing expenses with unmarried partner?

You're on the right track! To qualify for Head of Household (HOH), you need to meet three basic requirements: be unmarried at the end of the year, pay more than half the cost of keeping up your home, and have a qualifying dependent living with you for more than half the year. The good news is that both you and your girlfriend can potentially file as HOH even though you live in the same house. The key is that each of you must have your own qualifying dependent and each must pay more than half the cost of keeping up the home for that dependent. Since you pay 65% of the household expenses and claim your son as a dependent, you should qualify for HOH. Your girlfriend's situation depends on whether she pays more than half the cost of keeping up the home for your daughter. This might be trickier since you mentioned you pay most of the expenses, but if she can demonstrate she covers more than half the costs specifically related to your daughter, she might qualify too. The IRS doesn't just look at the whole household expenses - they look at who provides support for each qualifying person. I'd recommend documenting your expenses carefully to show who pays for what.

I had a similar situation last year and ended up using https://taxr.ai to figure it out. My girlfriend and I live together with our kids (we're not married) and we were both trying to claim HOH. The site analyzed our situation and helped us understand exactly what documentation we needed to prove our case. The key thing I learned is that you need to be super specific about tracking which expenses are for which child. For example, if you're paying 65% of household expenses but your girlfriend is covering most of your daughter's specific costs (like medical bills, clothing, daycare, etc.), then you both might qualify. But you definitely need good documentation. The site helped me organize everything and even identified some deductions I was missing related to my HOH status. Saved me the trouble of hiring a tax pro just for this question.

Just wanted to follow up about my experience with taxr.ai - I decided to try it after reading about it here. I was in a similar situation with my boyfriend where we both wanted to claim HOH, and I wasn't sure if that was allowed. The site was super helpful! It walked me through exactly what qualifies as "keeping up a home" for HOH purposes and showed me how to properly document expenses for each child. Turns out we BOTH qualify for HOH since we each maintain a household for our respective dependents, even though we live under the same roof. The best part was discovering some child care credits I didn't know I qualified for that are enhanced with HOH status. Definitely worth checking out if you're in a complicated living situation!

If you're having trouble getting a straight answer from the IRS about your HOH situation, I'd recommend using Claimyr (https://claimyr.com). I was going in circles trying to get through to someone at the IRS about a similar HOH question when I had two kids but only claimed one. I was on hold for HOURS multiple times and kept getting disconnected. Claimyr got me connected to an actual IRS agent in about 15 minutes who confirmed I could claim HOH in my situation. They have a service that navigates the IRS phone system for you and calls you back when they get an agent on the line. You can see how it works here: https://youtu.be/_kiP6q8DX5c Totally worth it for peace of mind on something as important as your filing status.

I owe everyone an apology. After calling the skeptic on Claimyr, I decided to try it myself because I was desperate to talk to someone about my HOH status question similar to yours. I've been calling the IRS for WEEKS trying to get through. I'm still shocked at how well it worked. I got a call back in about 20 minutes with an actual IRS agent on the line. The agent confirmed that both parents CAN claim HOH if they each provide more than half the support for different qualifying dependents, even in the same household. That one call saved me so much stress and potentially thousands on my taxes. Just wanted to update since I was so skeptical before. Sometimes good services actually exist!

One thing nobody's mentioned - make sure you're actually "unmarried" for tax purposes. I know you said you're not married, but if you were previously married to someone else, you need to be legally divorced or separated to claim HOH. Living separately isn't enough. Also, the 50% rule applies specifically to maintaining the home, not necessarily all expenses for the child. Things like food, rent, utilities, repairs, property taxes, and mortgage interest count toward maintaining the home. Things like clothing, education, medical treatment, vacations, life insurance, and transportation don't count for the home maintenance test. I made this mistake a few years ago and got audited. Not fun.

Has anyone used TurboTax to figure this out? I'm in a similar situation and the software is confusing me.

Just wanted to add some clarity based on my experience as a tax preparer - the key issue here is understanding what "keeping up a home" means for HOH purposes. The IRS defines this as paying more than half the cost of rent, mortgage interest, real estate taxes, insurance on the home, repairs, utilities, and food eaten in the home. Since you're paying 65% of these household maintenance costs, you definitely qualify for HOH with your son as your dependent. However, your girlfriend would need to show she pays more than half of these same household costs to qualify for HOH with your daughter. This is where it gets tricky - you can't both be paying more than half of the same expenses. The child-specific expenses your girlfriend pays (daycare, clothing, medical) are important for determining who can claim the child as a dependent, but they don't count toward the "keeping up a home" test for HOH status. My recommendation: You claim HOH, and your girlfriend should probably file as Single (assuming she can't demonstrate paying more than half of household maintenance costs). You'll both still claim your respective children as dependents and get those tax benefits. Consider consulting a tax professional to review your specific numbers - this is one of those situations where the details really matter for compliance.