Introduction: Expat Tax Montana Planning for British Families
The expat tax Montana position changed sharply in 2026, because the state cut its top income tax rate and rewrote its property tax at the same time. However, the two reforms pull in opposite directions for wealthy newcomers. The income tax fell to 5.65%, and long-term gains now bear only 4.1%. Meanwhile, second homes and high-value houses moved to a 1.9% property tax rate. Consequently, a British family in Bozeman, Big Sky, Whitefish or Missoula needs both sets of rules before it buys, sells or draws a pension.
At TaxYork, we prepare federal, state and UK returns for British founders, investors, physicians, remote executives and retirees across Montana. In our experience, most families arrive believing Montana is a low-tax state because it has no sales tax. In fact, the state taxes worldwide income, including every UK pension payment. Therefore this expat tax Montana guide explains what the state charges, the one relief most states refuse, and the evidence each claim needs.
Expat Tax Montana Basics: Two Income Tax Layers and a Property Layer
A British household resident in Montana faces two income tax layers. Federal tax reaches worldwide income, relieved by the foreign tax credit on IRS Form 1116. Montana then taxes the same worldwide income at up to 5.65%. In addition, HMRC keeps taxing UK rent and UK property gains. Finally, the property tax forms a third layer that now depends on how you use the house.
Who This Guide Is Written For
This guide addresses high-net-worth British nationals, dual national US UK families and accidental Americans living in Montana, plus Montana-domiciled Americans working in London. Specifically, it suits technology founders, remote senior executives, investors, physicians, ranch and business owners, and retirees holding UK property, pensions, ISAs or company shares. If that describes your household, the expat tax Montana rules below decide what the move really costs.
How Montana Compares With Our Other State Guides
Montana sits in the middle of the Mountain West range. To the south, Utah charges a flat rate on the same UK income. To the west, Washington has no income tax but charges up to 9.9% on large gains. In contrast, Texas taxes no income and adds community property rules, and New Hampshire taxes no personal income at all. As a result, the expat tax Montana bill is moderate on income, light on gains and heavy on a trophy house.
Montana Income Tax Rates for 2026 and 2027
Montana charges two rates on ordinary income and two lower rates on long-term gains. Furthermore, the 2025 legislature set separate schedules for 2026 and 2027. Therefore the year in which income arrives now matters for expat tax Montana planning.
The 2026 Ordinary Income Rates
For 2026, Montana charges 4.7% on the first 95,000 dollars of taxable income for a married couple filing jointly. Above that, the rate is 5.65%. For a single filer, the 4.7% band ends at 47,500 dollars. The Montana Department of Revenue confirms these figures. Notably, the top rate stood at 5.9% in 2025, so older expat tax Montana articles overstate the charge.
The 2027 Cut to 5.4%
In 2027, the top rate falls again to 5.4%. Moreover, the 4.7% band widens to 130,000 dollars for joint filers and 65,000 dollars for single filers. Consequently, a couple with 500,000 dollars of ordinary income saves roughly 1,200 dollars a year from the second cut. That saving is modest. However, it rewards deferring a bonus, a pension lump sum or a business distribution from late 2026 into early 2027.
Long-Term Capital Gains at 3% and 4.1%
Montana taxes net long-term capital gains under a separate schedule. The rates are 3.0% in the lower band and 4.1% above it. The gains bands match the ordinary income bands, reduced by your ordinary income. Hence a high earner pays 4.1% on every dollar of long-term gain. In contrast, short-term gains bear the ordinary rates. This split is the feature that makes expat tax Montana planning attractive in the year of a large disposal.
The Starting Point Is Federal Taxable Income
Since 2024, Montana has started its calculation from federal taxable income rather than adjusted gross income. The Montana tax simplification guidance explains the change. Therefore the federal standard deduction or your federal itemised deductions flow straight through. In addition, Montana filing status must match the federal one. As a result, a couple cannot file jointly with the IRS and separately with the state. Investopedia offers a plain summary of how taxable income is computed, which is now the base for every expat tax Montana calculation.
How Montana Taxes Your UK Income
Montana taxes a resident on all income, wherever it arises. Accordingly, UK pensions, rent, dividends, interest and gains all enter the state return. The expat tax Montana treatment of each differs slightly.
UK Pensions and the State Pension
Montana taxes UK pension income as ordinary income. A UK occupational pension, a SIPP drawdown and the UK State Pension all bear up to 5.65%. Under the treaty, the UK State Pension paid to a US resident is taxable only in America, so no UK tax arises to credit. Furthermore, HMRC explains how the State Pension works when you retire abroad, and payments to America receive no annual increase.
The Age 65 Subtraction
Montana repealed its old partial pension exclusion in 2024. Instead, each taxpayer aged 65 or over subtracts a fixed amount, set at 5,500 dollars and indexed from 2025. A couple who both qualify subtract double. However, that relief is small against a substantial UK pension. MoneyHelper sets out your options for taking a UK pension, and each option needs an expat tax Montana check before you choose. Therefore a retired British couple drawing 150,000 dollars a year should expect a Montana bill of about 5,000 dollars.
UK Rental Income
Montana taxes net UK rental profit at ordinary rates. The federal computation governs, so foreign residential buildings depreciate over 30 years under the alternative system. Meanwhile, HMRC still taxes the same rent, usually through the non-resident landlord scheme. Consequently, three authorities tax one profit, and the expat tax Montana layer arrives last. The federal credit normally absorbs the UK tax, and the state credit below may absorb any excess.
ISAs, UK Funds and Dividends
Montana gives an ISA no recognition, because the federal return gives it none. Interest, dividends and gains inside the wrapper are taxable each year. Moreover, UK unit trusts and investment trusts usually count as passive foreign investment companies, reported on IRS Form 8621. Notably, Montana taxes qualified dividends at ordinary rates. Only long-term gains receive the lower 4.1% rate, a detail many expat tax Montana summaries miss.
Selling UK Shares or a UK Company
A British resident of Montana who sells UK shares usually pays no UK tax, because HMRC does not tax non-residents on share gains. Therefore the gain bears federal tax, the 3.8% net investment income tax and Montana's 4.1%. In contrast, a UK property sale still carries UK tax, which the federal credit relieves. Founders should model the sale before completion, because the expat tax Montana charge on a ten million dollar gain is about 410,000 dollars.
The Montana Credit for UK Tax: A Rare Relief
Montana allows a resident a credit for income tax paid to another country. Most states refuse this entirely, as our guides to Illinois, Georgia and Colorado explain. However, the Montana credit comes with a strict federal coordination rule, and it sits at the heart of expat tax Montana planning for UK landlords.
What the Statute Allows
The Montana Code grants a credit for income tax imposed by and paid to another state or country on income the state also taxes. The Department of Revenue describes the credit for full-year and part-year residents. Specifically, the income must have its source in the other country, and the tax must be paid in full. In addition, the credit cannot exceed the Montana tax on that income.
The Federal Coordination Rule
Montana denies the credit for foreign tax to the extent you claimed the federal foreign tax credit on it. Therefore the state credit reaches only UK tax that the federal return could not use. For example, UK tax at 40% or 45% on UK rent often exceeds the federal tax on the same income. That excess normally sits unused as a carryover. Under the expat tax Montana rules, part of it may instead reduce the state bill.
The Limits and the Traps
Three limits apply. First, the credit is non-refundable and Montana allows no carryover, so an unused amount dies each year. Second, any foreign tax you deduct federally must be added back before the state credit applies. Third, the department's rule measures the excess after federal carrybacks and carryovers, so the computation needs care. Consequently, the claim belongs in a joined-up file, not a state return prepared in isolation.
Treaty Benefits Flow Through
Montana has no separate treaty rule. However, because the state starts from federal taxable income, an item the treaty removes from the federal return never reaches the state return. Similarly, a treaty-based position disclosed on IRS Form 8833 carries into Montana automatically. The US-UK treaty documents remain the source for each article, and the Chartered Institute of Taxation publishes technical commentary on cross-border rules for UK practitioners.
Montana Property Tax After the 2025 Reform
Montana rebuilt its residential property tax from 2026. The new system rewards owner-occupiers of modest homes and charges second homes and expensive houses more. For wealthy Britons, this is the largest expat tax Montana surprise.
The Homestead Reduced Rate
From 2026, a principal residence qualifies for tiered rates based on the statewide median home value. The rate starts at 0.76% on value up to the median, then rises through 0.90% and 1.10%. Value above four times the median, about 1.5 million dollars, bears 1.9%. These percentages produce taxable value, which local mill levies then convert into the bill. Therefore the cash cost is far below 1.9% of market value.
The 1.9% Rate on Second Homes
Every other residential property bears a flat 1.9% rate from 2026. That class covers ski homes, lake cabins and short-term rentals. Commentators estimate that a second home worth over 1.5 million dollars costs about 8,250 dollars a year more than before. Hence a British family that keeps its London home as the main residence pays the full rate on a Big Sky house.
The March Application Deadline
The reduced rate is not automatic for new owners. You must apply through the state homestead portal by 1 March, and you must own and live in the home for at least seven months of the year. Consequently, a family that buys in April pays the 1.9% rate for that whole year. In addition, long-term rentals let for 28 days or more qualify under a similar application.
No Sales Tax, but Resort Taxes
Montana has no general sales tax. However, resort communities charge their own local tax on lodging, restaurants and luxury goods. Big Sky and West Yellowstone charge 4%, and Whitefish charges 3%. Moreover, the state adds lodging taxes totalling 8% on short stays. Owners who let a home to holidaymakers must therefore register and collect these charges, which form a separate expat tax Montana compliance strand.
Residency, Second Homes and Montanans in London
Montana treats you as a resident if you are domiciled there or maintain a permanent place of abode there. The second test catches people who never intended to become residents. Accordingly, expat tax Montana exposure can begin with a house purchase.
The Permanent Place of Abode Test
The Montana residency guidance lists the factors the department weighs. They include a Montana driving licence, voter registration, a resident hunting or fishing licence, vehicle registration and where you receive professional services. Notably, a resident fishing licence is a common mistake among second-home owners. Therefore a Briton who summers in Whitefish should buy the non-resident licence and keep a diary of days.
Part-Year Residents in the Year of Arrival
In the year you move, Montana taxes income received while you live there plus any Montana-source income from the rest of the year. Hence the timing of a UK bonus, a share sale or a pension lump sum matters. Specifically, a gain completed before you establish a home in Montana stays outside the state. Furthermore, the federal residency start date and the state date need not match, so document both in your expat tax Montana file.
Montana-Domiciled Americans Working in London
An American who leaves Bozeman for a London posting remains a Montana resident until a new domicile replaces the old one. However, Montana's starting point helps. The foreign earned income exclusion claimed on IRS Form 2555, worth up to 132,900 dollars for 2026, reduces federal taxable income and therefore state income. In contrast, the federal credit does not reduce state income. Consequently, earnings above the exclusion stay taxable in Montana until you break domicile properly.
Foreign Account Reporting and Catching Up
State tax is only part of the picture. British families in Montana also carry federal reporting duties that have no UK equivalent. Moreover, the penalties attach to missed forms, not to missed tax, so they sit outside the expat tax Montana calculation entirely. The AICPA publishes guidance on tax practice standards that every preparer should follow.
Why Gaps Are Common in Montana
Montana has few preparers who see UK assets regularly. As a result, we often find a missed FBAR, missed reporting of a UK pension or ISA, and UK funds entered as ordinary shares. You must report UK accounts on the FBAR through FinCEN's filing system once the combined balance passes 10,000 dollars. In addition, IRS Form 8938 applies above higher thresholds.
Putting Missed Years Right
Missed US tax returns and missed foreign account reports can usually be corrected before the IRS makes contact. Depending on the facts, the route may be amended returns, delinquent information returns or the IRS Streamlined Filing procedures. Furthermore, any federal amendment requires an amended Montana return, because the state starts from federal taxable income. Our FBAR and FATCA reporting service prepares the federal and state corrections together.
Case Study: A Software Founder in Bozeman
This illustrative case shows how the expat tax Montana rules combine. The figures are rounded and use 2026 rates.
The Income
James and Priya are British citizens with green cards. They moved from London to Bozeman in 2024. In 2026, James earns 420,000 dollars from his software company. They also receive 30,000 dollars of UK dividends and 48,000 dollars of net rent from a Kensington flat. Additionally, James sells UK listed shares for a long-term gain of 300,000 dollars. HMRC charges about 6,800 dollars on the rent after their personal allowances.
The Montana Bill
Their ordinary income totals 498,000 dollars. After the 32,200 dollar federal standard deduction, 465,800 dollars remains. Montana charges 4.7% on the first 95,000 dollars, which is 4,465 dollars. The remaining 370,800 dollars bears 5.65%, which is 20,950 dollars. Furthermore, the 300,000 dollar gain bears 4.1%, which is 12,300 dollars. Therefore the state bill is about 37,700 dollars.
The Credit, the Property and the Lesson
The federal return absorbs the whole 6,800 dollars of UK tax, because federal tax on the rent exceeds it. Consequently, no state credit arises this year. In 2027, the same ordinary income would cost about 1,170 dollars less. Meanwhile, their 2.4 million dollar home qualifies for the homestead tiers only because they applied by 1 March. Above all, the case shows that the expat tax Montana saving sits in gains and in paperwork, not in the headline rate.
How TaxYork Can Help
TaxYork provides comprehensive tax preparation and compliance for British families in Montana and for Montanans in Britain. We prepare every return from one set of figures, so the federal, state and UK positions agree.
Expat Tax Montana Returns Prepared as One File
We prepare the federal return, Montana Form 2 and the UK Self Assessment return together. Specifically, we compute the federal credit first, then test whether any UK tax remains for the state credit. In addition, our US tax return preparation for expats covers Forms 1116, 8621, 8833 and 8938. Our tax treaty optimisation service documents each treaty position, so the expat tax Montana file survives an enquiry from either side.
Business Owners, Founders and Property Owners
Founders and investors need more than an annual return. Therefore we model disposals before completion, comparing the 4.1% state charge across 2026 and 2027. Furthermore, we track the homestead application, the seven-month occupation test and the resort tax registrations for let property. We also coordinate estimated payments, so a large gain does not trigger underpayment interest on the expat tax Montana bill.
Conclusion
Montana is neither a tax haven nor a high-tax state. The income tax now peaks at 5.65% and falls to 5.4% in 2027. Long-term gains bear only 4.1%. Moreover, the state offers a credit for UK tax that the federal return cannot use, which most states refuse. However, UK pensions are fully taxable, qualified dividends receive no lower rate, and a second home now bears the 1.9% property rate. Ultimately, the expat tax Montana outcome depends on timing, residency evidence and returns prepared as one file.
Contact Us
If you hold UK income or assets and live in Montana, or you are a Montanan working in Britain, speak to our team before your next filing deadline. You can book a consultation with a US-UK specialist today. Alternatively, email hello@taxyork.com or call 020 3488 8606. We will review your federal, state and UK position together and tell you exactly which returns and reports you need.
Disclaimer
This article provides general information only and does not constitute tax, legal or financial advice. Tax rules in the United States, Montana and the United Kingdom change frequently, and their application depends on your individual circumstances. Rates and thresholds reflect our understanding at October 2026. You should obtain professional guidance before acting on any matter discussed here. TaxYork accepts no liability for any loss arising from reliance on this article.