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Capital gains tax on a second property

Fahad ZarCrypto tax accountant, licensed and regulated by the AAT. MSc Accounting and Finance, BPP University London. Six years reconciling wallet and exchange histories for UK filings.

Published 14 August 2026· Reviewed against gov.uk 25 August 2026· 4 min read·Capital gains tax

Sixty days. Sell a second property at a gain and that is how long you have from completion to report it and pay the tax, on a standalone return most sellers have never heard of until the deadline has passed. Everything else about second-property gains is ordinary arithmetic. The deadline is the part that hurts people.

What you will pay

A second home, a buy-to-let, an inherited house you kept, none of it gets Private Residence Relief, so the gain is taxable from the first pound above your £3,000 allowance. Residential gains are taxed at 18% inside your remaining basic rate band and 24% above it, your income eats the band first, and the same disposal routinely spans both rates. The GOV.UK property pages carry the official rules, and our calculator does the two-rate split from your income.

The gain is smaller than the price difference

Sale price minus purchase price overstates nearly every property gain, because the allowable costs are generous and half-forgotten. On the way in: legal fees, survey, and the stamp duty you paid at purchase, which on a second property was substantial. On the way out: agent’s commission and legal fees again. And in between, capital improvements, the extension, the loft conversion, the new kitchen where none existed, count in full.

The line that matters is improvement against maintenance. Replacing a knackered boiler is maintenance, already relieved against rental income if you were letting, and not deductible here. Adding a bathroom that did not exist is improvement, deductible. Landlords who claimed works as repairs against rent cannot claim the same works again at sale, and HMRC does check for the double dip. Fifteen years of invoices decide these questions, which is the unglamorous reason to keep them.

The 60 day return

The report and pay deadline runs from completion, not exchange, and it is a real return with a computation behind it, filed through HMRC’s property account with the tax paid at the same time. Miss it and late filing penalties and interest attach to a deadline you did not know existed. Conveyancers do not file it for you, and many never mention it, which is precisely how organised people with accountants still get caught.

The disposal then also goes on your normal Self Assessment return, where the year’s full picture, your other gains, your losses, settles the final figure with credit for what you paid.

The planning that is still available

Before completion, options exist. Transfers between spouses carry no gain, so a jointly held sale uses two allowances and two sets of rate bands, and moving a share to a lower-earning spouse before sale is standard practice done properly and early. Timing a completion just after 5 April moves the tax a full year into the future and can catch a second allowance. Realised losses elsewhere in your portfolio offset property gains too, crypto losses included, the cross-asset planning our loss harvesting guide covers. After completion, the only planning left is compliance.

Fahad Zar

Crypto tax accountantAAT licensed 1010475

• AAT Licensed Accountant and MAAT, licence 1010475
• MSc Accounting and Finance, BPP University London
• Six years inside digital asset accounting, across several crypto tax firms
• Practises through Zar Enterprises Ltd, ICO registration ZC225094
• Supervised for anti-money laundering by the AAT

What matters to me is that the number on the return is true, whatever it turns out to be.

Whether this is worth a conversation

Most people who read this page do not need an accountant. A few do.

• Your gains are near the £3,000 line
• You have swapped tokens and doubt the numbers
• You have old losses nobody ever claimed

If you sold one holding once and the figures are plain, file it yourself. Paying someone to check arithmetic you can do is not a service.

If one of these is you, the first look costs nothing.

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