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Capital gains tax calculator for buy to let

Selling a rental property? Estimate the capital gains tax you'll owe, with the £3,000 allowance, your allowable costs and the 18% and 24% rates worked out against your income band.

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Enter your sale price, purchase price and income to see your estimated capital gains tax.

Information, not tax advice. BTL Insight is not a tax adviser. This calculator estimates capital gains tax from the standard published rates and allowances (verified June 2026) for property held in personal names. It cannot account for every relief or special case. Capital gains tax rates and the annual exempt amount can change at any Budget. For the official rules and your own situation, see GOV.UK: Tax when you sell property and CGT rates and allowances, and speak to a qualified tax adviser or accountant before relying on any figure.

Understanding capital gains tax on a buy to let

The figures and rules below summarise the official guidance from GOV.UK on selling property and HMRC's capital gains tax rates and allowances. It is general information to help you understand how the tax works, not personal tax advice.

How the gain is worked out

Capital gains tax is charged on your profit, not the sale price. The starting point is the sale price minus what you originally paid, minus your allowable costs.

What you can deduct:

  • Stamp duty, legal and survey fees paid when you bought
  • Estate agent and legal fees when you sell
  • Capital improvements such as an extension or new kitchen

What you cannot deduct: mortgage interest, and routine repairs or maintenance.

The allowance and the 18% / 24% rates

Everyone has an annual exempt amount of £3,000, deducted from the gain before tax. What's left is added on top of your income to find the rate:

  • 18% on the part of the gain that sits within your remaining basic-rate band
  • 24% on any part above it

Because the gain stacks on your income, a larger gain often falls partly in each band, so this calculator splits it and applies both rates, exactly as HMRC does.

Reporting and paying: the 60-day rule

For a UK residential property you must report and pay within 60 days of completion, through an HMRC Capital Gains Tax on UK property account. Miss it and there's an automatic penalty plus interest, so it pays to know the figure before you complete.

Keep your purchase and sale completion statements, plus receipts for any improvements, as your evidence.

Ways the bill can be lower

A few situations reduce or remove the tax. This is general information, not advice, but the common ones:

  • Joint ownership: spouses and civil partners each have their own £3,000 allowance and bands, so two owners can shelter more.
  • You once lived there: Private Residence Relief covers that period plus the final 9 months.
  • Releasing cash without selling: a remortgage to draw out equity doesn't trigger capital gains tax at all.
  • Held in a company: a limited company pays Corporation Tax on the gain, not capital gains tax. See the letting strategy comparison.

Common questions about capital gains tax on a buy to let

How is capital gains tax on a buy to let calculated?

Start with the gain: sale price minus what you originally paid, minus allowable buying and selling costs and capital improvements. Deduct your £3,000 annual exempt amount. The remaining taxable gain is added on top of your income, the part within your remaining basic-rate band is taxed at 18%, and anything above it at 24%. A large gain can straddle both rates.

What is the CGT rate on a rental property in 2026?

For residential property the rates are 18% for the part of the gain within your remaining basic-rate income tax band and 24% above it, with a £3,000 annual exempt amount. These are confirmed by HMRC for the 2026 to 2027 tax year.

When do I have to pay it?

You must report and pay capital gains tax on a UK residential property within 60 days of completion, using an HMRC Capital Gains Tax on UK property account. Missing the deadline triggers an automatic penalty and interest.

Can I avoid CGT by selling one buy to let and buying another?

No. The UK has no rollover relief for residential buy-to-let, so reinvesting the proceeds in another rental makes no difference, the tax is still due within 60 days. Business Asset Rollover Relief only applies to qualifying trading assets, and letting residential property counts as an investment, not a trade. If your aim is to free up cash, a remortgage releases equity without triggering CGT.

Can I reduce CGT by transferring to my spouse?

Transfers between spouses or civil partners are treated as "no gain, no loss", so no CGT arises on the transfer itself. Because each person has their own £3,000 allowance and their own income bands, owning jointly can use two allowances and may tax part of the gain at 18% rather than 24%. Get tax advice on the most efficient way to do this before you sell.

Do I pay CGT if I lived in the property first?

If the property was your main home for part of your ownership, Private Residence Relief exempts that proportion of the gain plus the final 9 months. The period it was let stays taxable. Lettings relief now only applies where you shared occupancy with the tenant, so it rarely helps a standard buy-to-let. See HMRC on selling your home.

Do I pay CGT if I sell through a limited company?

No. A company doesn't pay capital gains tax, it pays Corporation Tax on the gain under different rules. This calculator is for property held in personal names. For company-held property, check the figures with an accountant. Deciding between the two in the first place? Our limited company or personal name tool covers the trade-offs, including the cost of moving a property in.

Do I still get the allowance if I've sold another property this year?

The £3,000 annual exempt amount is a single allowance for the whole tax year, the UK tax year running from 6 April to 5 April, not one per property. If you've already used some of it against another gain this year, enter that amount in the "CGT allowance already used this tax year" field and the calculator reduces the allowance accordingly.

What if I have capital losses from previous years?

Losses from earlier disposals that you've reported to HMRC can be carried forward and set against this gain. Enter them in the "capital losses brought forward" field. They're deducted after your annual allowance, and only by enough to bring the gain down, so you don't waste the £3,000 allowance. Any losses you don't use stay available for future years.

What if I've made other capital gains this year?

Other gains in the same tax year (from shares or another property, for example) sit below this gain and use up your basic-rate band first, so more of this gain can fall into the 24% band. Enter the taxable amount of those other gains in the "other taxable gains this tax year" field and the calculator adjusts the 18% / 24% split accordingly.

What records do I need to keep?

Keep your completion statements from buying and selling, plus invoices for any capital improvements and your professional fees. HMRC can ask you to evidence every figure used to work out the gain, and good records are also how you make sure you claim every allowable cost.