CGT on HMO Disposals: How Is It Different from Standard Buy-to-Let?

Capital gains tax on the disposal of a house in multiple occupation is charged in the same way as on a standard buy-to-let property: at 18% or 24% on the gain in 2026/27, with a £3,000 annual exempt amount, and no Business Asset Disposal Relief unless the HMO is genuinely run as a trade. The practical differences lie in how the gain is calculated, what counts as an allowable cost, and how the property was taxed while you held it. Understanding the HMO tax rules UK landlords face on sale helps you avoid an unexpected bill and report correctly within HMRC's deadlines. This guide, written by Blue Tick Accountants, a Guildford-based UK tax advisory and accountancy practice, explains how CGT on HMO disposals works and where it diverges from an ordinary rental sale, covering rates, allowable costs, SDLT, and reporting.

Key Takeaways

• Capital gains tax on an HMO disposal is charged at 18% within the basic rate band and 24% above it for residential property in 2026/27, the same rates as standard buy-to-let.
• The capital gains tax annual exempt amount is £3,000 per individual for 2026/27, so joint owners can shelter £6,000 of gain between them.
• Gains on UK residential property, including HMOs, must be reported and the tax paid within 60 days of completion using HMRC's Capital Gains Tax on UK Property service.
• Most HMO income is taxed as property income rather than trading income, which means Business Asset Disposal Relief and its 18% rate usually do not apply on disposal.
• The 5% Stamp Duty Land Tax surcharge on additional dwellings applies when a landlord buys an HMO, increasing the acquisition cost that later reduces the taxable gain.
• Capital improvements such as fire safety works and en-suite conversions can be added to the property's base cost and reduce the CGT payable on sale.

How is CGT on an HMO disposal calculated in 2026/27?

Capital gains tax on an HMO disposal is calculated by deducting the purchase price, buying and selling costs, and qualifying capital improvements from the sale proceeds, then applying the 18% and 24% rates of 18% and 24% for 2026/27. The gain is added on top of your income to decide how much falls in the basic rate band at 18% and how much sits above it at 24%. Each owner also deducts the £3,000 annual exempt amount first.

Consider a landlord who bought an HMO for £320,000, spent £15,000 on a compliant fire safety and en-suite refurbishment, and sold it for £430,000 with £6,000 of legal and agent fees. The gain is £430,000 minus £320,000, £15,000 and £6,000, leaving £89,000. After the £3,000 exemption, £86,000 is taxable, and a higher rate taxpayer paying 24% would owe £20,640.

Why does HMO income classification affect the disposal?

How a house in multiple occupation is taxed during ownership shapes the relief available on sale, because most HMOs are treated as an investment property business rather than a trade. HMRC generally taxes HMO rents as property income, not trading profits, even where the landlord cleans communal areas or provides basic services. This matters at disposal: Business Asset Disposal Relief, which reduces the capital gains tax rate to 18% on qualifying business sales up to a £1,000,000 lifetime limit in 2026/27, only applies where the property forms part of a genuine trade, such as certain serviced or hotel-style operations. For the typical HMO landlord, HMRC treats the sale as a standard residential disposal taxed at 18% or 24%.

What costs can an HMO landlord deduct against the gain?

An HMO landlord can deduct the original purchase price, Stamp Duty Land Tax paid on acquisition, legal and survey fees, estate agent and conveyancing costs on sale, and the cost of capital improvements from the disposal proceeds. Capital improvements are works that enhance the property beyond its original state, such as adding en-suites, installing a compliant fire alarm and door system, or extending the building. Routine repairs and redecoration cannot be claimed against the gain because they are revenue costs, deductible instead against rental income during ownership. Licensing fees paid to the local authority are also a revenue expense, so they reduce your income tax rather than your CGT. Keeping records that separate capital works from repairs is essential, because the distinction changes both your annual tax and your disposal bill.

Where the line falls between a revenue repair and a capital improvement governs the annual return as much as the disposal, and our guide to which landlord costs are deductible draws it.

How do SDLT and reporting deadlines fit the HMO picture?

Stamp Duty Land Tax and the 60-day reporting rule bookend the ownership of an HMO and both affect the tax you ultimately pay. When a landlord buys an HMO, the 5% additional dwellings surcharge applies on top of standard residential SDLT rates for 2026/27, because it is a second or further property, and that SDLT is added to the acquisition cost to reduce the eventual gain. On disposal, an HMO is UK residential property, so any taxable gain must be reported and the CGT paid within 60 days of completion through HMRC's Capital Gains Tax on UK Property service, separately from the self-assessment return. Missing the 60-day deadline triggers penalties and interest, so planning the disposal in advance is worthwhile.

For a complete overview of how houses in multiple occupation are taxed from purchase to sale, see our guide to HMO tax rules.

Frequently Asked Questions

Do you pay more capital gains tax on an HMO than a normal buy-to-let?

No, capital gains tax on an HMO is charged at the same residential property rates as a standard buy-to-let: 18% within the basic rate band and 24% above it for 2026/27. An HMO is not taxed at a higher CGT rate because it has multiple tenants. The main differences are in how allowable costs and licensing are treated during ownership, not the disposal rate.

Can an HMO landlord claim Business Asset Disposal Relief?

Usually no, because most HMOs are treated by HMRC as a property investment business rather than a trade, and Business Asset Disposal Relief only applies to genuine trading businesses. Relief may be available where the operation is run as a qualifying trade, such as a serviced or hotel-style arrangement with substantial services. Specialist advice is important before assuming the 18% relief rate applies.

How long do you have to report CGT on an HMO sale?

You have 60 days from the completion date to report the gain and pay the capital gains tax on a UK residential property disposal, including an HMO, using HMRC's Capital Gains Tax on UK Property service. This deadline is separate from your self-assessment return. Late reporting results in HMRC penalties and interest charges on the tax due.

Does the 5% stamp duty surcharge apply when buying an HMO?

Yes, the 5% Stamp Duty Land Tax surcharge on additional dwellings applies when a landlord buys an HMO in 2026/27, because it is a second or further residential property. The surcharge sits on top of standard residential SDLT rates. The SDLT paid becomes part of the acquisition cost and reduces the chargeable gain when the property is eventually sold.

How Blue Tick Can Help

Blue Tick Accountants advises landlords across the UK on the full tax life of a house in multiple occupation, from the SDLT on purchase through annual property income to capital gains tax on disposal. The team can calculate your likely CGT, identify every allowable cost and improvement, and make sure the gain is reported within the 60-day window to avoid penalties. Head to our website and book a meeting now.

Conclusion

Capital gains tax on an HMO disposal follows the standard residential rates of 18% and 24% for 2026/27, so the real savings come from claiming every allowable cost and reporting within 60 days. Any HMO landlord planning a sale should gather full records of purchase costs, SDLT, and capital works early, then take advice before completion so the gain is calculated and reported correctly the first time.

About the Author

This guide was written by Leon, founder of Blue Tick Accountants, a Guildford-based UK tax advisory and accountancy practice that helps landlords, limited company owners and the self-employed across the UK. It was last reviewed for the 2026/27 tax year.

This article is intended for general informational purposes only and does not constitute tax, legal, or financial advice. Tax rules are subject to change and their application will depend on your individual circumstances. You should always seek advice from a qualified professional before taking action. Blue Tick Accountants accepts no liability for decisions made on the basis of this content.