How to fairly split tax liability from a previous joint filing during divorce?
I'm going through a divorce right now and trying to figure out a fair way to split our tax bill from last year when we filed jointly. My soon-to-be-ex works two full-time jobs (neither employer knows about the other) and pulled in around $210k last year. I'm only making about $85k from my single job. When we filed our 2024 taxes jointly, we got hit with a massive $28k tax bill. She's claiming I had less withholding on my paychecks which is why we owed so much, and she came up with some division of the payment that feels really unfair to me. I don't have access to all our tax documents anymore since she moved out and took them. Is there a fair or standard way to determine who should be responsible for what portion of a joint tax liability when you're splitting up? I'm worried I'm paying way more than my fair share considering the income disparity.
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Elijah Brown
Tax professional here. This is actually a common situation during divorces. When you file jointly, you're both equally liable for the entire tax bill regardless of who earned what. However, for divorce negotiations, there are a few ways to fairly determine who "caused" what portion of the liability: First, you could have a tax professional prepare "mock" separate returns using your individual income information to see what each of you would have owed filing separately. This comparison often gives you a clear picture of who contributed most to the joint liability. Another approach is to calculate the percentage of total household income each person contributed and use that same percentage to divide the tax liability. In your case, if the total household income was $295k and you contributed $85k, that's about 29%, which would make your portion around $8,100 of the $28k bill.
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Zoe Walker
•Thanks for this info! The percentage approach makes a lot of sense. I didn't even consider doing mock separate returns. Would a regular tax preparer be able to do that for me even without having our full joint return? I only have my W-2 and some basic info.
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Elijah Brown
•Yes, a tax preparer can create a mock separate return with just your W-2 and basic information, though having your full joint return would make the comparison more accurate. They'd need to make some assumptions about which deductions would apply to you. For the percentage approach, make sure you're using adjusted gross income rather than just gross earnings. This accounts for pre-tax contributions that affect tax liability. If your divorce attorney is involved, they might suggest having this analysis included in your settlement discussions.
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Maria Gonzalez
I went through something similar last year and found this amazing tool at https://taxr.ai that really helped sort out my tax liability situation. I uploaded our previous joint returns and my individual W-2s, and it analyzed exactly how much of our joint tax bill was attributable to my income vs my ex's. The system breaks down the tax liability based on income sources, deductions claimed, and credits that applied to each person. It even gave me a detailed report I could share with my attorney that showed I was actually overpaying based on my ex's calculation. Saved me over $7,000 in the divorce settlement!
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Natalie Chen
•How accurate is this tool? I'm in a similar situation but my ex is claiming that since I took some side gig income that wasn't properly withheld, I should pay 70% of our joint tax bill even though I only made about 40% of our total income.
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Santiago Martinez
•Does it handle situations where one spouse has self-employment income? My wife had a small business and I'm wondering if the tool can properly attribute the self-employment taxes to her portion rather than splitting them between us.
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Maria Gonzalez
•The tool is remarkably accurate - it uses the same calculations the IRS uses but separates the inputs by individual. It clearly identified which income sources contributed to the additional tax liability in my case, including insufficient withholding. It absolutely handles self-employment income correctly. That's actually one of its strengths - it properly attributes self-employment tax to the spouse who earned that income, rather than treating it as a joint liability. The report breaks down exactly how each income source (W-2, 1099, business income, etc.) affects your total tax obligation.
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Natalie Chen
Just wanted to update - I tried the taxr.ai site mentioned above and it was incredibly helpful! I uploaded our old joint return plus my W-2s, and within minutes I had a clear breakdown showing I was only responsible for about 35% of our tax bill based on my income and withholding. The report showed exactly how much of the tax liability came from each income source and even factored in the tax brackets correctly. My ex had been trying to get me to pay 50% despite making significantly less. The report was detailed enough that when I showed it to my lawyer, she immediately incorporated it into our settlement negotiations. Totally worth it for the peace of mind alone!
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Samantha Johnson
If you need to get copies of your previous tax returns to do this analysis correctly, I'd highly recommend using https://claimyr.com to connect with the IRS. I spent WEEKS trying to get through to the IRS myself to get copies of our past returns that my ex "lost," and kept hitting brick walls. Used Claimyr and got connected to an IRS agent in about 15 minutes who helped me request all my past returns. You can see how it works in this video: https://youtu.be/_kiP6q8DX5c - basically they wait on hold with the IRS for you and call you when an agent picks up. Saved me hours of frustration and I got the documents I needed to properly figure out my fair share of our past tax liability.
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Nick Kravitz
•Wait, so this service just waits on hold for you? Couldn't you just put your phone on speaker and do something else while waiting? Why would anyone pay for this?
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Hannah White
•Is this even legit? How do they guarantee you'll actually get through? I've tried calling the IRS like 20 times and never get a human, just endless loops of automated messages.
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Samantha Johnson
•It's not just about putting your phone on speaker - the IRS hold times can be 2-3 hours or more, and they often disconnect calls after long waits. With Claimyr, you don't have to keep your phone tied up or worry about disconnections. You just go about your day until they text you that an agent is on the line. Yes, it's completely legitimate. They don't guarantee you'll get through on the first try, but they keep trying until they do connect you with a human agent. What they're doing is using a system that can handle multiple calls simultaneously and knows how to navigate the IRS phone tree optimally. When I used it, I had tried calling 8 times on my own with no success, but they got me through on their first attempt.
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Hannah White
I just have to say I was completely wrong about Claimyr from my skeptical comment above. After getting nowhere with the IRS for weeks, I decided to give it a shot. Not only did they get me through to an IRS agent within about 40 minutes (when I had never been able to reach anyone), but the agent was able to pull up all my past 3 years of joint returns. I was able to get copies mailed to me, which I then used to figure out exactly how much of our joint liability was from my income versus my ex's. Turns out I was responsible for only about 30% of what we owed, not the 65% my ex was trying to make me pay! Having the actual returns made all the difference in proving this to our mediator.
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Michael Green
Something else to consider - if your ex has two jobs and neither employer knows about the other, she might not be having enough taxes withheld from either paycheck. The withholding tables assume each job is your only job, so having two jobs without adjusting withholding usually results in significant underwithholding. So if she's making $210k between two jobs but each employer is withholding as if she only makes about $105k, she's probably not having enough withheld to cover her tax bracket. This could be a major source of your joint liability that has nothing to do with your withholding.
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Zoe Walker
•That makes a lot of sense actually. She always refused to adjust her W-4 forms when I suggested it. Is there any way to prove this was the cause of our big tax bill rather than my withholding being insufficient?
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Michael Green
•You can definitely prove this by having a tax professional create a withholding analysis. They would look at both of your W-2 forms, which show exactly how much was withheld from each paycheck throughout the year. The analysis would compare the actual withholding to what should have been withheld based on your total income and tax brackets. This will clearly show if her dual employment without proper withholding adjustment was the primary cause of the shortage. Most tax pros can prepare this kind of analysis in about an hour, and the documentation would be very useful for your divorce settlement negotiations.
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Mateo Silva
Just wondering has anyone actually called the IRS directly about this? When my brother got divorced, he contacted the IRS and requested what's called "innocent spouse relief" which can separate the tax liability in certain situations.
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Victoria Jones
•Innocent spouse relief probably won't apply in this situation. That's typically for cases where one spouse did something fraudulent or didn't report income without the other spouse's knowledge. In this case, it sounds like everything was reported correctly, they just owe a lot. The IRS does offer something called "separation of liability relief" though, which might be helpful after the divorce is finalized. But you usually need to wait until after the divorce is done to apply for that.
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