Do You Pay Capital Gains Tax When You Sell Your House in Montana?

One of the first questions Montana homeowners ask before selling is: "Will I owe capital gains tax?" It's a smart question, and the good news is that most people selling their primary home owe little or nothing thanks to a generous federal exclusion. But the details matter — especially for inherited homes, rentals, and second properties. Here's what Montana sellers should understand about capital gains tax in 2026.

The federal home-sale exclusion (the big one)

The most important rule for most sellers: the IRS lets you exclude a large amount of gain on the sale of your primary residence. If you've owned and lived in the home as your main residence for at least two of the last five years, you can exclude up to:

• $250,000 of gain if you're single, or
• $500,000 of gain if you're married filing jointly.

Important: this applies to your gain (roughly, sale price minus what you paid plus improvements), not the sale price. So a couple who bought a Montana home for $250,000 and sells for $600,000 has a $350,000 gain — fully covered by the $500,000 exclusion, meaning no federal capital gains tax. This is why most primary-home sellers owe nothing.

How Montana taxes capital gains

Montana does not have a separate capital gains tax — instead, capital gains are taxed as part of your state income. However, Montana has historically offered a capital gains tax credit that reduces the effective rate on net capital gains. For any gain that exceeds the federal exclusion (or on a property that doesn't qualify for it), Montana income tax may apply, reduced by that credit. Rates and credit details can change year to year, so confirm the current figures with a Montana tax professional.

The key point: if your primary-home sale is fully covered by the federal exclusion, there's typically no taxable gain flowing to your Montana return either.

Inherited homes: the stepped-up basis

If you inherited a Montana home, you get a major tax advantage: a stepped-up basis. Your cost basis becomes the home's fair market value on the date the previous owner died — not what they originally paid. So if a home bought decades ago for $60,000 is worth $400,000 when you inherit it, your basis is $400,000. Sell near that value soon after, and your taxable gain is often minimal. See our guide on selling an inherited house in Montana for more.

Rentals and second homes are different

The primary-residence exclusion does not apply to rental properties, second homes, or vacation properties. Selling those can trigger capital gains tax, and for rentals, depreciation recapture may also apply if you claimed depreciation. Some investors use a 1031 exchange to defer gains by rolling into another investment property. These situations are more complex — talk to a tax professional. See also our guides on selling a vacation rental and selling a house with tenants.

Does a cash sale change the tax picture?

No. How you sell — cash sale, traditional listing, fast or slow — doesn't change the capital gains rules. What matters is whether the home is your primary residence, your gain amount, and your basis. A cash sale simply gets you to closing faster; the tax treatment is the same.

Bottom line

Most Montana homeowners selling their primary residence owe no capital gains tax, thanks to the federal exclusion of up to $250,000 (single) or $500,000 (married). Inherited homes benefit from a stepped-up basis, while rentals and second homes can trigger tax and depreciation recapture. Montana taxes gains as income but softens it with a credit. When in doubt, a quick conversation with a tax professional gives you certainty before you sell.