You've sold a rental property, the money has landed, and you assume the tax sorts itself out in January with your tax return. For most buy-to-let sales, that assumption is wrong, and it can cost you penalties.
If you make a taxable gain on UK residential property, you usually have to report it and pay the Capital Gains Tax (CGT) within 60 days of completion. That's a separate, faster process from your Self Assessment return, and it catches a lot of landlords off guard.
This is a practical, step-by-step guide to the 60-day rule: who it applies to, how the "Capital Gains Tax on UK property" account works, what you'll need to hand, and a worked example with current figures. It's written for landlords selling a buy-to-let, not for someone selling their own home.
What is the 60-day CGT rule for buy-to-let?
If you sell a UK residential property and there's CGT to pay, you must report the gain and pay the tax within 60 days of the completion date, using HMRC's online "Capital Gains Tax on UK property" account. This applies to completions on or after 27 October 2021.
It's worth being clear on why this exists. Capital Gains Tax used to be reported and paid only through Self Assessment, sometimes 18 to 22 months after a sale. For UK residential property, HMRC now wants the tax much sooner. The 60-day window is the result.
A few things to fix in your head from the start:
- The clock runs from the completion date, not the exchange date and not the date the money reaches your account.
- The deadline is 60 days for completions on or after 27 October 2021. (For completions between 6 April 2020 and 26 October 2021, the window was 30 days. You'll still see "30-day rule" written online, but it's out of date.)
- This is a standalone report and payment. If you're in Self Assessment, you'll often report the same gain again on your tax return, and the 60-day payment is then set against your final bill.
This post is about the reporting mechanism. If you want to understand how the gain itself is calculated, what counts as an allowable cost, or how letting and private residence reliefs interact, read our guidance for landlords alongside this one.
Who has to file a 60-day CGT report?
Answer capsule: UK residents must file a 60-day report when they sell UK residential property and there's CGT to pay. Non-UK residents must report every disposal of UK property or land, even when no tax is due.
For a UK resident landlord, the test is whether there's a taxable gain after deducting your costs and your annual exempt amount. If the sale leaves you with tax to pay, you report and pay within 60 days. If the gain is fully covered by reliefs or the annual exempt amount and there's nothing to pay, a UK resident generally doesn't need to make a 60-day report (though you may still report the gain on your Self Assessment return).
The position is stricter for non-residents. If you're not a UK resident, you must report disposals of UK property or land even if you have no tax to pay on the disposal.
A few common situations:
- Standard buy-to-let sold at a profit - report and pay within 60 days.
- Buy-to-let sold at a loss - no CGT to pay, so a UK resident usually has no 60-day report to make, but keep the records and claim the loss on Self Assessment.
- A property that was once your main home then let out - private residence relief may reduce or remove the gain. If tax still remains, the 60-day report applies.
- Jointly owned property - each owner reports their own share separately, on their own account.
If you're unsure whether a relief wipes out your gain, work it out before you assume there's nothing to file. Getting that judgement wrong is exactly where penalties creep in.
When exactly does the 60-day clock start?
The 60 days run from the date of completion, which is when ownership legally transfers and you get the sale proceeds. That's the date your solicitor or conveyancer will confirm on the completion statement.
This trips people up because property sales have two key dates:
- Exchange of contracts - the point at which the sale becomes legally binding. For CGT, this is the date of disposal that fixes which tax year the gain falls in.
- Completion - the day the deal actually finishes and money changes hands. This is the date the 60-day reporting clock runs from.
In practice, exchange and completion are often the same day or only a week or two apart. But where there's a long gap, note both dates carefully. The disposal date (exchange) decides the tax year and which rates and allowances apply; the completion date starts your 60-day deadline.
Count calendar days, not working days. Weekends and bank holidays are included. If day 60 falls on a weekend, don't gamble on it, aim to file and pay before then.
What are the CGT rates on a buy-to-let in 2025/26?
A buy-to-let is residential property, so it's taxed at the residential rates, which are higher than the rates on most other assets.
For 2025/26 and 2026/27, the CGT rates on residential property gains for individuals are:
| Taxpayer position | CGT rate on residential property | Tax year |
|---|---|---|
| Gain falling within your basic-rate band | 18% | 2025/26 and 2026/27 |
| Gain falling above the basic-rate band (higher/additional) | 24% | 2025/26 and 2026/27 |
The annual exempt amount, the slice of gains you can make tax-free each year, is £3,000 for individuals for both 2025/26 and 2026/27.
How the bands work in practice: you stack your taxable gain on top of your taxable income for the year. The part of the gain that sits within your remaining basic-rate band is taxed at 18%, and anything above it at 24%. The basic-rate band covers taxable income up to £37,700 (above the personal allowance) for 2025/26, so a landlord with a decent income and a sizeable gain will often pay 24% on most or all of it.
For 2025/26 and 2026/27, the personal allowance is £12,570 and the higher-rate threshold starts at £50,271 of total income.
These are the figures you'll need before you can complete a 60-day report, because the report asks you to estimate the tax due. Our Capital Gains Tax calculator can help you sanity-check the number before you file.
How do you report it? The step-by-step process
You report through HMRC's online "Capital Gains Tax on UK property" account. It's separate from the main Self Assessment system, even though both sit behind your Government Gateway login.
Here's the process, start to finish.
Step 1: Gather your figures
You'll need:
- The dates you bought and sold (acquisition and disposal/completion dates).
- What you paid for the property and what you sold it for.
- Allowable costs: stamp duty land tax on purchase, legal and estate agent fees, and the cost of capital improvements (not repairs).
- Any reliefs you're claiming, such as private residence relief if it was once your home.
- Your estimated taxable income for the year, so you can work out how much of the gain is taxed at 18% versus 24%.
Step 2: Set up your "Capital Gains Tax on UK property" account
Sign in with your Government Gateway user ID and set up a Capital Gains Tax on UK property account if you don't already have one. You'll get an account reference number for the property disposal.
If you'd rather not file online, or you're digitally excluded, HMRC provides a paper "Capital Gains Tax on UK property" form instead.
Step 3: Report the gain
Enter the figures, the dates, your costs, any reliefs and the gain. The service calculates the estimated CGT due based on the income and rate information you give it.
Step 4: Get your payment reference and pay
After you submit, HMRC issues a 14-digit payment reference number that starts with "X". You use that reference to pay the tax. Both the report and the payment must be done within the 60 days.
Step 5: If you use an agent
You can authorise an accountant to file the report for you, but the authorisation step has its own setup and can take a little time. With a hard 60-day deadline, don't leave that to the last week. If you'd like us to handle the report end to end, our tax advisory services cover exactly this.
Illustrative example: a higher-rate landlord's 60-day report
Illustrative example. Priya, a higher-rate taxpayer, sells a buy-to-let flat. It completes on 10 May 2025 (in the 2025/26 tax year). The property was never her home, so no private residence relief applies.
Her figures:
| Item | Amount |
|---|---|
| Sale price | £300,000 |
| Less: original purchase price | £210,000 |
| Less: stamp duty land tax and legal fees on purchase | £8,000 |
| Less: estate agent and legal fees on sale | £4,500 |
| Less: cost of a new fitted kitchen (capital improvement) | £7,500 |
| Gain before allowance | £70,000 |
| Less: annual exempt amount (2025/26) | £3,000 |
| Taxable gain | £67,000 |
Priya's income already uses up her basic-rate band, so the whole taxable gain is taxed at the higher residential rate of 24% for 2025/26.
CGT due: £67,000 x 24% = £16,080.
Because completion was on 10 May 2025, Priya must report the disposal and pay the £16,080 through her Capital Gains Tax on UK property account by 9 July 2025 (60 days after completion). She'll then report the same gain on her 2025/26 Self Assessment return, with the £16,080 already paid set against her final position.
(Figures are illustrative. The point is the method and the deadline, not Priya's specific numbers.)
How does the 60-day report fit with Self Assessment?
The 60-day report doesn't replace your tax return. For most landlords in Self Assessment, the gain gets reported twice: once in the 60-day report, then again on the Self Assessment return for that tax year.
Think of the 60-day payment as a payment on account of the CGT. When you complete your Self Assessment return:
- You recalculate the gain with the full year's actual figures (your real income for the year may shift how much falls at 18% versus 24%).
- The CGT already paid through the 60-day report is credited against the figure on your return.
- If you overpaid, you can be due a refund; if you underpaid, the balance is due with your return.
This matters because the 60-day report uses an estimate of your income for the year. If your income turns out differently, the final split between 18% and 24% can change, and the Self Assessment return is where it all squares up.
One genuinely useful habit: keep a copy of the 60-day calculation and the HMRC payment reference. When it's time to prepare the tax return, you'll need both to reconcile the figures cleanly.
What if you file or pay late?
Miss the 60-day deadline and HMRC can charge a late filing penalty, a late payment penalty and interest. They're separate, and they stack.
For the late filing of a UK property CGT return, HMRC's penalty regime starts with a fixed penalty once the return is late, with further penalties building up the longer it stays outstanding (including daily penalties and additional charges once a return is 6 and 12 months late). The exact amounts depend on how late you are and the tax involved, so check HMRC's penalties factsheet for the current detail before relying on a figure.
Separately, if you pay the tax late, late payment penalties and interest apply on the unpaid amount. Interest runs from the due date until you pay.
The practical takeaway: the penalties are real and avoidable. The single most common cause we see isn't refusal to pay, it's landlords simply not knowing the 60-day clock had started. Diary the deadline on completion day and you remove the risk.
Your 60-day deadline calendar
To make the timing concrete, here's how the 60-day window falls for a few example completion dates. Always count from your own completion date; this table is just to show the shape of it.
| If completion is on... | Report and pay by... |
|---|---|
| 10 May 2025 | 9 July 2025 |
| 1 September 2025 | 31 October 2025 |
| 1 January 2026 | 2 March 2026 |
| 6 April 2026 | 5 June 2026 |
Day counts are calendar days including weekends and bank holidays. If your day 60 lands awkwardly, file early rather than testing it.
Frequently asked questions
Is it 30 days or 60 days to report CGT on property?
It's 60 days for completions on or after 27 October 2021. The 30-day window applied to completions between 6 April 2020 and 26 October 2021. Any current buy-to-let sale uses the 60-day rule, so ignore older "30-day" guidance.
Do I still report the gain on my tax return if I've done the 60-day report?
Usually yes, if you're in Self Assessment. You report the same gain again on your tax return, and the CGT already paid through the 60-day report is credited against your final bill. The Self Assessment return is where the figures are finalised with your actual income for the year.
What if my buy-to-let sells at a loss?
If there's no CGT to pay, a UK resident generally has no 60-day report to make. Keep full records and claim the loss on your Self Assessment return so it can be set against other gains. Non-residents must still report the disposal even where no tax is due.
Does the 60-day clock start at exchange or completion?
Completion. Exchange of contracts is the disposal date that fixes the tax year, but the 60-day reporting and payment deadline runs from the completion date, when ownership transfers and you receive the proceeds.
What CGT rate will I pay on a buy-to-let?
For 2025/26 and 2026/27, residential property gains are taxed at 18% to the extent they fall within your basic-rate band and 24% above it. The £3,000 annual exempt amount is deducted first. Most higher-rate landlords pay 24% on most of the gain.
Can my accountant file the 60-day report for me?
Yes. You can authorise an agent to report on your behalf through the Capital Gains Tax on UK property service, but the authorisation has its own setup, so arrange it early given the tight deadline.
Book a free Tax Health Check →
Get the 60-day report right, first time
The 60-day report is one of the most missed deadlines in property tax, and the penalties are entirely avoidable. If you've sold, or you're about to sell, a buy-to-let, we can calculate the gain, file the report and handle the payment reference inside the window. Talk to a Zmartly accountant about your tax advisory needs and we'll take it from there.
