Capital gains tax on a second property
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.
Second property questions
How much is capital gains tax on a second home?
18% within your unused basic rate band, 24% above it, on the gain after costs and the £3,000 allowance. The rate split depends on your income in the year of sale.
Does the 60 day rule apply if there is no tax to pay?
Where relief or losses mean nothing is due, a UK resident generally has no 60 day return to file. If any tax is due, the clock is real. Non-residents file within 60 days regardless.
Can I deduct the stamp duty I paid when I bought?
Yes, purchase stamp duty is part of your acquisition cost, along with legal and survey fees. Sellers forget it constantly, and on second properties it is rarely small.
What if I once lived in the property?
Then part of the gain may be covered by Private Residence Relief for your years of residence plus the final nine months, and the computation blends this post with the main home rules. Mixed-use histories are exactly where professional computation pays.
If a completion date is already in the diary, the 60 day clock is about to start. Get the computation built before it does. Our free review will tell you the shape of the liability and what is still fixable.
