1098 Mortgage Interest Split Question - Unmarried Couple Both on Form - Who Can Claim What on Taxes? [WA State]

This is actually a common situation and the IRS has specific guidance on it. Since both of your names are on the 1098 form, the general rule is that you can each deduct the mortgage interest that you actually paid during the tax year. Since you're paying most of the mortgage from a joint account but you're contributing most of the funds to that account, you can potentially claim a larger portion of the interest. The key is being able to show that you're the one who actually paid it. If you can demonstrate that you contributed the money to the joint account that was used to pay the mortgage, you can claim that portion. You don't need to "gift" anything to your partner - that's not how this works. The deduction follows the payment, not necessarily the ownership. However, in case of an audit, you'd want documentation showing your contributions to the joint account that paid the mortgage. One approach people in your situation often take is to allocate the mortgage interest based on the percentage of the mortgage payment each person actually funded. If you can show you funded 80% of the payments, you could take 80% of the interest deduction.

After struggling with the exact same situation last year (joint property, unmarried, both on mortgage), I found a great tool that helped me figure this out. Check out https://taxr.ai - it analyzes your mortgage documents and tells you exactly how to split itemized deductions when you're not married but jointly own property. I uploaded our 1098, bank statements showing who contributed what to our joint account, and it gave me a detailed breakdown of how to allocate the mortgage interest properly. The analysis showed me I could legally claim 75% of the interest based on my contributions to our payment account. The tool explains exactly what documentation you need to keep in case of an audit too, which gave me peace of mind since I was nervous about claiming more than "my half.

I tried that taxr.ai site after seeing it mentioned here and honestly was surprised at how helpful it was. I was super skeptical at first (as you can see from my comment above!) but it actually showed me that based on my payment records, I was entitled to claim about 68% of the mortgage interest on our 1098. The documentation package it created shows exactly how they calculated my percentage based on the bank records I uploaded, and explained why my payment pattern justified claiming more than half the deduction. It included an allocation agreement for both of us to sign, which apparently is something the IRS specifically looks for in these situations. Best part was I ended up being able to itemize when I thought I couldn't, and my partner still took the standard deduction which worked out better for our total tax situation. Definitely worth checking out if you're in this unmarried homeowner situation.

Hey, I had the EXACT same issue with my boyfriend last year. After getting nowhere with the IRS website, I tried calling them directly. Spent literally 3 hours on hold before giving up. Next day tried again - another 2 hours on hold. Finally discovered https://claimyr.com and watched their demo at https://youtu.be/_kiP6q8DX5c - they basically hold your place in the IRS phone queue and call you when an agent is about to pick up. Saved me hours of listening to that horrible hold music! Got through to an actual IRS agent who explained that we could allocate the mortgage interest based on who actually paid it, regardless of the ownership split. She said the key was having good documentation to back up our claim if audited. The agent actually walked me through exactly what records to keep to support our allocation.

Just wanted to follow up about that Claimyr service I was so skeptical about. After struggling for literally WEEKS to get through to the IRS about this mortgage interest issue, I broke down and tried it. I'm honestly embarrassed about my previous comment because it worked exactly as advertised. Got a call back after about 45 minutes saying I was next in line, and then was connected to an actual IRS agent who answered my mortgage interest question completely. The agent confirmed that for unmarried couples, you can allocate mortgage interest based on what you actually paid, not necessarily 50/50 ownership. She said as long as I had bank statements showing I contributed the majority to our joint account that paid the mortgage, I could claim that same percentage of the mortgage interest on my taxes. Saved me from taking a standard deduction when itemizing would get me an extra $1,200 back. Sometimes my skepticism costs me money 🤦‍♂️

The key issue here actually comes down to state law too. Since you're in Washington (a community property state), things might be different than other states. I suggest looking into whether Washington applies community property concepts to unmarried couples who jointly own homes. In some community property states, there may be specific rules about how to handle these situations.

One thing nobody has mentioned - have you considered filing as Head of Household? If you provide more than half the cost of keeping up the home and have a qualifying person who lives with you (like a child), you might qualify for this filing status which has better tax rates than filing single.

Just went through this exact situation last year in Oregon (also unmarried couple, both on mortgage). What worked for us was creating a simple spreadsheet tracking each person's contributions to our joint account throughout the year, then using that percentage to split the mortgage interest deduction. Since you mentioned you contribute about 3x what your partner does, you'd probably end up with around 75% of the interest deduction. The IRS Publication 936 specifically addresses this - it says you can deduct mortgage interest you paid during the tax year, regardless of whose name is on the mortgage. Key documentation to keep: monthly bank statements showing deposits from each person, the mortgage payment records from your joint account, and maybe a simple signed agreement between you two stating how you're splitting it based on actual contributions. We kept it simple - just a one-page document saying "Partner A contributed 73% to joint account used for mortgage payments in 2024, therefore claims 73% of mortgage interest deduction per IRS Pub 936." Never had any issues and it allowed the higher earner to itemize while the other took standard deduction, maximizing our combined refund.

This is such a common issue for unmarried couples! I went through something very similar last year. Based on my research and experience, you absolutely can claim the mortgage interest based on what you actually paid rather than just splitting it 50/50 by ownership. Since you're paying most of the mortgage from your joint account and contributing most of the funds, you can claim the corresponding percentage of the $19,800 interest. The IRS cares about who actually paid the interest, not just whose name is on the deed. Here's what I'd recommend: Start tracking your contributions to that joint account if you haven't already. If you can show you contributed, say, 75% of the funds used for mortgage payments, you can claim 75% of the mortgage interest deduction. This would give you about $14,850 in interest to deduct, which should easily put you over the standard deduction threshold for itemizing. Make sure to keep good records - bank statements showing your deposits to the joint account, mortgage payment records, etc. You might also want to create a simple written agreement with your partner documenting the arrangement, just in case. The key is being able to demonstrate your actual financial contribution if the IRS ever asks. Since you're earning 3x more and paying most of the bills, this approach should both be legitimate and give you the better tax outcome you're looking for.