CGT 60-Day Reporting for Landlords: What Triggers It and What Happens If You Miss the Deadline

What the 60-day rule actually is

Capital Gains Tax on UK residential property used to sit quietly inside annual Self Assessment. You sold a buy-to-let in May, declared the gain in your January return eight months later and settled the bill alongside the rest of your tax. That changed on 6 April 2020, when HMRC introduced a 30-day reporting window. From 27 October 2021, following the Autumn Budget that year, the window stretched to 60 days for completions on or after that date. The 60-day rule is what every UK landlord works to today.

Two things have to happen inside that window. You report the disposal through HMRC's online Capital Gains Tax on UK property account, which sits separately from the main Self Assessment portal. And you pay the tax that the return calculates. Both have the same deadline: 60 calendar days after the completion date shown on your TR1 or equivalent transfer document. The exchange date does not start the clock. Completion does.

Most landlords we onboard have not heard of the account until their conveyancing solicitor mentions it on the day of completion. By then, the clock has already started. The rule does not care that your professional adviser has not been engaged yet, that your records are still in three different filing cabinets or that the bank statement showing the deposit on the purchase ten years ago is no longer in your possession. Sixty days is sixty days.

Which disposals trigger the rule, and which slip past it

Not every property sale puts you inside the 60-day system. The trigger is narrow: a disposal of UK residential property where a Capital Gains Tax liability actually arises. Three filters apply.

First, the asset must be UK residential. Commercial property, shares in property companies, REIT units, cryptoassets and overseas property all fall outside the 60-day rule and stay inside annual Self Assessment. Mixed-use property is partly inside: the residential element gets apportioned and reported on the 60-day return, the commercial element does not.

Second, the disposal must produce a gain that actually creates a tax bill after Private Residence Relief, the annual exempt amount of £3,000 for 2025/26 and any available losses. A sale fully covered by Private Residence Relief because you lived in the property as your main home for the whole period of ownership produces no taxable gain and no 60-day filing obligation. A small gain that sits entirely within the £3,000 annual exempt amount produces no taxable gain either. And a loss obviously creates no liability.

Third, you have to be UK resident. Non-UK residents have a separate, broader rule: every disposal of UK property must be reported within 60 days regardless of whether tax is due, and that has applied to residential property since April 2015 and to commercial since April 2019. If you spend more than half the year overseas, the threshold for reporting drops to zero and the system treats you very differently. The remainder of this guide focuses on UK residents.

How the tax is actually calculated

The gain itself is simple in principle: sale proceeds minus base cost minus allowable expenses minus reliefs minus the annual exempt amount. Each line carries detail that can shift the result by thousands of pounds.

Sale proceeds is the gross figure on completion, before estate agent fees, solicitor fees, conveyancing and any other selling costs come out. Those costs sit in allowable expenses and reduce the gain separately. Buyer side fees never enter your calculation.

Base cost is what you paid for the property when you acquired it, plus any capital improvements made during your period of ownership. Capital improvements means structural additions like an extension, a loft conversion or a new kitchen that was not there before. Routine maintenance, redecoration and like-for-like replacement boilers do not count as capital and are not part of base cost. Stamp Duty Land Tax paid on the original purchase, the legal fees, the survey and the search fees all add to base cost.

Allowable expenses on the sale side include the estate agent commission, solicitor fees, EPC charges, removal costs that genuinely relate to the disposal and any small capital works done specifically to enable the sale. They reduce the chargeable gain pound for pound.

Reliefs are the biggest swing factor. Private Residence Relief covers the period the property was your main residence, plus a final 9 months for any property that was at any point your main home. Letting Relief, narrowed sharply in April 2020, now only applies where you shared the property with the tenant during the let period. Most landlords have no claim. After Private Residence Relief and any letting element come out, the £3,000 annual exempt amount applies last.

The rate then depends on where the gain sits inside your income bands. Add your total income for the year to the taxable gain. The slice within the basic rate band of £37,700 is taxed at 18 percent. The slice above it is taxed at 24 percent. A higher-rate income earner with a £40,000 gain on a buy-to-let will pay the full 24 percent. A part-time earner with a small pension and the same gain may pay 18 percent on a portion before crossing into the 24 percent band.

The penalty ladder if you miss the deadline

HMRC's penalty regime for late 60-day returns is the same one that applies to late Self Assessment returns. The amounts climb in steps, with each step triggered by how many months past the deadline you are.

Day 61 is the first trigger. A £100 fixed penalty lands automatically the moment the deadline passes, regardless of whether tax was due. Filing one day late costs £100 even if your final CGT bill turns out to be £200. We have seen landlords assume that filing on day 62 will be forgiven because the gain itself was small. It is not. The penalty is calculated on the obligation to report, not on the size of the tax.

Three months late is the next trigger. From day 91, HMRC can impose daily penalties of £10 per day for up to 90 days, capped at £900. Combined with the initial £100, that takes the running total to £1,000 before any tax-geared charges have kicked in. The daily penalty only applies on prior written notice, and HMRC has not always used it for residential property 60-day returns, but the power exists and the National Audit Office has flagged it as a likely future enforcement focus.

Six months late is the third trigger. An additional 5 percent of the tax due or £300, whichever is greater, is added at day 181. A property gain that produced a £15,000 CGT bill picks up £750 here. A smaller £5,000 bill picks up the £300 floor.

Twelve months late is the final step in the standard ladder. Another 5 percent or £300 (whichever greater) is added at day 361. Behavioural penalties of up to 100 percent of the unpaid tax can apply on top if HMRC considers the failure deliberate and concealed.

Interest runs separately on the unpaid CGT itself from day 61. HMRC's late payment interest rate sits at 2.5 percent above the Bank of England base rate. Across the May 2026 base rate, that puts late payment interest in the order of 7 to 8 percent annually. A £15,000 CGT bill paid 18 months late accrues around £1,700 of interest on top of the penalty stack.

The CGT on UK property account and what it asks for

The reporting itself happens through a dedicated HMRC online service called the Capital Gains Tax on UK property account, separate from Self Assessment and separate from your Personal Tax Account home page. You access it through Government Gateway, and the first time you log in you will need to add the service to your account. The portal accepts agent authorisation, so a chartered accountant can file on your behalf if you grant them access through your agent code.

The return asks for the property address, the date of completion, the disposal proceeds, the original acquisition cost, allowable purchase and sale costs, any reliefs claimed and a calculation of the chargeable gain. It also asks for your estimated income for the full tax year so HMRC can work out what proportion of the gain falls at 18 percent and what proportion at 24 percent. That estimate is provisional and can be refined later through Self Assessment.

You can save the return and come back to it, file it in stages and amend it after submission until the corresponding Self Assessment for the year has been filed. Payment is by debit card, bank transfer or Direct Debit, and the payment reference number is generated on submission. Keep the receipt: HMRC's record matching of CGT payments to specific 60-day returns has occasionally lagged in practice, and the payment reference is what unblocks any dispute.

Side-by-side: 60-day return vs annual Self Assessment

What this means for you, in five practical steps

Five concrete moves turn a stressful 60-day window into a controlled one. None are difficult, but the order matters and the prep work has to begin before the property is even on the market.

1. Pull your base cost evidence the day you list. The original completion statement from your purchase, the SDLT 5 certificate, the original solicitor invoice, the survey and search fees and any invoices for capital improvements since. Most landlords have a file somewhere, but it is rarely complete. Rebuilding it from scratch the week after completion is the single most common cause of missed 60-day deadlines we see.

2. Estimate your income for the full tax year before completion. Rental income, employment income, dividend income, pension drawdown and any other gains. The figure determines how much of the property gain falls at 18 percent and how much at 24 percent. A rough estimate is fine for the 60-day return and is refined later on Self Assessment.

3. Engage your accountant before exchange, not after completion. The 60-day clock starts at completion. If your accountant is appointed on day 30, you have lost half the window. We onboard landlords mid-sale almost every week. Earlier is always better.

4. Set the tax aside on completion day. The CGT comes out of the sale proceeds, not out of next month's rent. Treat the 60-day return as a payment that has already been earmarked. Many landlords spend the sale proceeds on a deposit for the next property before the 60-day deadline lands, then have to refinance the move to pay HMRC.

5. File before day 50, not day 60. An early filing leaves time to fix any HMRC query, gives your accountant headroom for a final review and removes the cliff-edge risk of a technical issue on the portal at hour 59. The deadline is a backstop, not a target.