The 60-Day CGT Deadline: How to File on Time

60-day Capital Gains Tax rule: what it is and who it applies to

Before 6 April 2020, landlords and property investors who sold a residential property reported the gain once — on their annual Self Assessment tax return, up to 22 months after the disposal. That changed with the introduction of the 60-day reporting and payment window.

Under the current rules, any individual who disposes of a UK residential property where CGT is payable must:

• File a standalone online return using HMRC's Report and Pay Capital Gains Tax on UK Property service
• Pay the CGT estimated as due at that point
• Do both within 60 days of the completion date

The rule applies to residential property only — buy-to-let properties, second homes, inherited properties, and any dwelling that is not (or was not always) your main home. It does not apply to commercial property disposals or to sales where no CGT is owed, for example where the gain falls within your Annual Exempt Amount (£3,000 for 2024/25 onwards) or is fully covered by Private Residence Relief.

For a broader grounding in how CGT arises when you sell a rental property, read our guide to CGT on rental property in the UK.

The obligation to file the 60-day return exists separately from, and in addition to, your annual Self Assessment tax return. Both must be completed. The tax paid under the 60-day report is credited against your Self Assessment liability, so you will not pay the same CGT twice — but omitting either filing is an error HMRC will pursue.

When does the 60-day clock start? Completion, not exchange

The most common timing mistake is using the exchange of contracts date instead of the completion date. Exchange is the point at which buyer and seller are legally committed to the transaction. Completion is the date on which legal ownership transfers and the purchase price is paid. These can be days or even months apart.

The 60-day clock begins on the completion date. If your solicitor confirms completion on 1 June, your 60-day deadline is 31 July (the day 60 days later, inclusive of the first day). If completion and exchange happen simultaneously — which is common in auction sales — that shared date is day zero.

To know your exact deadline in seconds, calculate your CGT and get your 60-day deadline using the LandlordTaxAi CGT Calculator. Enter the completion date and the tool displays your precise filing deadline alongside the estimated tax.

60-day CGT deadline penalties: what HMRC charges

HMRC's penalty regime for missing the 60-day deadline escalates in three stages. HMRC's official penalties guidance sets out the full schedule.

Interest begins accruing on any unpaid CGT from day 61 — the day after the deadline. The interest rate is set by HMRC and is linked to the Bank of England base rate. On a CGT bill of £20,000, missing the deadline by three months could easily add several hundred pounds in interest alone before the tax is paid.

If you have a reasonable excuse for missing the deadline — for example, a serious illness or bereavement — HMRC may cancel the fixed penalty if you contact them promptly. However, interest on late-paid tax is charged regardless of excuse.

How to file your 60-day CGT return: step by step

You file through HMRC's dedicated online service — not through your annual Self Assessment return. HMRC's guidance on reporting and paying Capital Gains Tax provides the authoritative instructions. The steps below summarise the process for a typical residential disposal.

Step 1 — Create or log in to your Government Gateway account

Go to gov.uk/report-and-pay-your-capital-gains-tax and sign in with your Government Gateway user ID and password. If you do not yet have a Government Gateway account, create one — the verification process takes a few minutes but must be done before you can file. Do not leave this to day 58.

Step 2 — Gather the information you need

Before you start the return, have the following to hand:

• Your Unique Taxpayer Reference (UTR)
• Your National Insurance number
• The completion date of the disposal
• The sale price (or market value if gifted or sold at undervalue)
• The original acquisition price and acquisition date
• Allowable costs: solicitor fees, stamp duty on purchase, estate agent fees on sale, capital improvement costs
• Whether the property was ever your main residence (for Private Residence Relief)
• Whether you are a basic-rate or higher/additional-rate taxpayer (CGT rates differ: 18% and 24% for residential property as of 2024/25)

If Private Residence Relief applies to part of the gain — for example, because you lived in the property before letting it — read our guide to the Private Residence Relief calculator to understand how the relief is apportioned.

Step 3 — Work out your gain

Your chargeable gain is broadly: sale price, minus acquisition price, minus allowable costs. The Annual Exempt Amount (£3,000 for 2024/25 onwards) is then deducted. The remaining gain is taxed at 18% (basic rate) or 24% (higher/additional rate) for residential property. Losses from other disposals in the same tax year can also reduce the gain.

The easiest way to arrive at an accurate figure before you file is to calculate your CGT and get your 60-day deadline using our CGT Calculator. It walks through each component and shows the tax split by rate band.

Step 4 — Submit and pay

Once you have completed the online return, HMRC will show you the amount due. Pay immediately by bank transfer, debit card, or through your online banking using HMRC's bank details. Keep your HMRC payment reference. The payment clears more quickly if made by Faster Payments — do not use cheque if you are close to the deadline.

Common mistakes that cause landlords to miss the deadline

Confusing the 60-day report with Self Assessment

This is the most widespread error. Many landlords — and even some accountants unfamiliar with property disposals — believe that declaring the gain on the annual Self Assessment return is sufficient. It is not. The 60-day return is a separate, earlier obligation. You must do both.

For a full explanation of the Self Assessment process and how it interacts with MTD for landlords, see our MTD for landlords guide.

Using the exchange date instead of completion date

As covered above, the deadline runs from completion. If there is a three-week gap between exchange (15 May) and completion (5 June), the deadline is 4 August — not 14 July. Using exchange adds three weeks of false comfort and can push you past the real deadline.

Missing allowable costs

Allowable costs reduce the chargeable gain directly. Landlords frequently omit solicitor fees and stamp duty from the original purchase, estate agent fees on the sale, and the cost of improvements made to the property during ownership. Note that ordinary repair and maintenance costs — which you deduct from rental income — are not allowable for CGT. Only enhancement expenditure (capital improvements that add to the property's value) qualifies.

Not having a Government Gateway account before the deadline

Creating a Government Gateway account and verifying your identity takes time. HMRC may need to send a letter with a code, which can take up to seven days. If you are ten days from the deadline and do not have an account, contact HMRC immediately. There is a telephone filing option in exceptional circumstances, but the online route is strongly preferred.

Assuming a loss means no obligation

If the disposal genuinely produces no CGT liability — because there is no gain, the gain is within the Annual Exempt Amount, or Private Residence Relief extinguishes it entirely — there is no 60-day filing obligation. However, you must be certain of this before deciding not to file. If in doubt, file a nil-tax return within the 60 days.

Joint ownership: each owner files separately

Where a property is owned jointly — between spouses, civil partners, or other co-owners — each owner is treated as having made a separate disposal of their own share. Each person has their own obligation to file a 60-day return and pay their own share of the CGT. Each person's 60-day clock runs from the same completion date.

One owner cannot file on behalf of the other. Both individuals need their own Government Gateway accounts. Both must have their own UTR and National Insurance number. Each will apply their own Annual Exempt Amount and pay CGT at their own marginal rate.

Married couples and civil partners who hold property in equal shares each report 50% of the gain. If the beneficial ownership is unequal — for example, 60/40 — each person reports their respective proportion. A declaration of trust (Form 17 lodged with HMRC) is required to establish a non-50/50 split for tax purposes.

Use the CGT Calculator to model each owner's position separately, especially where the co-owners are in different tax bands.

Non-residents: separate rules apply

Non-UK residents who dispose of UK residential property are subject to the Non-Resident Capital Gains Tax (NRCGT) regime, which has its own reporting requirements. The 60-day reporting window applies to non-residents in the same way as UK residents — but additional rules govern the calculation of the gain, specifically the rebasing of the property to its April 2015 value (or April 2019 value for indirect disposals).

Non-residents must file a 60-day return even if the disposal results in no tax liability due to a treaty or other exemption. The filing obligation exists regardless. This is a stricter requirement than for UK residents, where a no-liability disposal carries no mandatory filing obligation.

If you are a non-resident disposing of UK property, you should seek specialist advice given the additional complexity.

What to do if you have already missed the 60-day CGT deadline

Do not delay further. The penalties increase at six months and twelve months, and interest accrues daily from day 61. The right course of action is to file the late return as quickly as possible and pay the CGT owed, including any accrued interest shown in your HMRC account.

Once you have filed, HMRC will issue a penalty notice for the £100 fixed penalty (and any further penalties if you are more than six months late). If you have a reasonable excuse — serious illness, bereavement, or another exceptional circumstance — you can appeal the penalty by contacting HMRC within 30 days of the penalty notice. Submit your appeal in writing and keep a copy. HMRC's penalties guidance explains the appeal process.

Even if your penalty appeal is successful, interest on the late-paid tax will still be charged. Interest is not cancelable because it compensates HMRC for the time-value of money — it is not a penalty in the strict sense. Pay the tax as soon as possible to stop interest accruing.

You will still need to include the disposal in your annual Self Assessment return for the tax year in which the disposal occurred. The tax paid under the 60-day return (or the late return) will be credited against your Self Assessment liability, so you should not end up double-paying — but both filings remain required.

Frequently asked questions