What Are the Penalties for Missing the 60-Day Property CGT Deadline?

Selling a property but missed the 60-day Capital Gains Tax deadline? Learn what penalties apply, how interest is calculated, and what to do if you have filed late.

Introduction

When you sell a residential property in the UK that is not your main home, you may have to pay Capital Gains Tax (CGT) on any profit made. Since April 2020, HMRC requires you to report and pay this tax within 60 days of completing the sale.

Missing this deadline can result in penalties and interest charges, even if you pay the tax shortly after. Understanding how these penalties work and what to do if you miss the deadline can help you avoid unnecessary costs and stay compliant with HMRC rules.

What Is the 60-Day Property CGT Rule?

The 60-day rule applies when you sell or dispose of a UK residential property that is not fully covered by Private Residence Relief (the relief for your main home).

You must:

  1. Calculate the gain and estimate the tax due.

  2. Report the sale using HMRC’s Capital Gains Tax on UK Property online service.

  3. Pay the CGT within 60 days of completion.

This rule applies to:

  • Second homes

  • Rental properties

  • Holiday homes

  • Inherited properties that have been let or not used as your main residence

The 60-day deadline begins the day after completion, not the day the property sale is agreed.

What Happens If You Miss the 60-Day Deadline?

If you fail to report and pay the CGT within 60 days, HMRC can impose both penalties and interest on the amount due. The penalties increase the longer you delay.

Even if no CGT is due, you must still submit a return if the property qualifies. Failing to do so can result in penalties for late filing.

Penalty Structure for Missing the 60-Day Deadline

HMRC applies penalties based on how late your submission is. The system is similar to the one used for late Self Assessment tax returns.

  1. Missed by up to 6 months:

    • Fixed penalty of £100 for missing the initial 60-day deadline.

  2. More than 6 months late:

    • Additional penalty of £300 or 5% of the CGT owed, whichever is greater.

  3. More than 12 months late:

    • Another £300 or 5% of the CGT owed, whichever is greater.

In total, late filing penalties can easily exceed £700, especially if the tax owed is significant.

Interest on Late Payment

In addition to fixed penalties, HMRC charges interest on the unpaid CGT from the date it should have been paid. The interest rate is variable and set slightly above the Bank of England base rate (currently around 7.75% in 2025).

Interest continues to accrue until the payment is made in full. Even a short delay can result in extra costs, so it is important to act as soon as possible if you have missed the deadline.

Example Scenario

Let’s say James sells a buy-to-let property on 1 June 2024 and makes a taxable gain of £80,000. His CGT bill is £14,400.

  • His 60-day deadline to report and pay is 31 July 2024.

  • He forgets and files the return on 15 December 2024, over 4 months late.

HMRC charges him:

  • A £100 fixed penalty for missing the deadline.

  • Interest on the £14,400 CGT owed for 137 days.

If he waited until February 2025 (over 6 months late), he would also face a £300 penalty or 5% of the tax owed (£720), whichever is greater.

Reasonable Excuses for Late Filing

HMRC may waive penalties if you have a reasonable excuse for missing the 60-day deadline. However, the standard is high, and you must prove that circumstances genuinely prevented you from meeting the deadline.

Examples of reasonable excuses include:

  • Serious illness or bereavement during the filing period.

  • HMRC’s online service being unavailable or malfunctioning.

  • Incorrect professional advice (for example, being told you had longer to file).

Lack of awareness of the 60-day rule is not normally accepted as a valid reason. If you think you have a genuine excuse, you must provide evidence when appealing the penalty.

How to Report Late if You Have Missed the Deadline

If you realise you have missed the 60-day window, act quickly:

  1. Log in to or register for HMRC’s CGT on UK Property account.

  2. Submit your return as soon as possible, even if you cannot pay right away.

  3. Pay the CGT due or contact HMRC to discuss a Time to Pay arrangement.

By submitting and paying promptly, you can limit additional penalties and reduce the amount of interest charged.

How to Avoid Missing Future Deadlines

  • Prepare early: Begin calculating your CGT as soon as you accept an offer on the property.

  • Use professional help: An accountant or tax adviser can ensure your return is accurate and submitted on time.

  • Set reminders: The 60-day countdown starts from completion, not exchange. Mark the date in your calendar.

  • Keep records: Maintain documents such as purchase contracts, valuation reports, and improvement receipts to make calculations easier.

The Role of an Accountant

An accountant can:

  • Calculate your capital gain accurately, including allowable costs and reliefs.

  • Prepare and file your CGT return on time.

  • Ensure you pay the correct amount and avoid unnecessary penalties.

  • Help you appeal any fines if you had a reasonable excuse.

Using professional help is particularly useful if you are unsure how to calculate your gain or have multiple property sales in a tax year.

Conclusion

Missing the 60-day property CGT deadline can lead to significant penalties and interest charges. HMRC imposes a £100 fine immediately after the deadline, followed by additional penalties for longer delays.

If you have missed the deadline, submit your return and pay as soon as possible to reduce extra costs. In future, plan ahead and consider professional advice to ensure all reporting is done on time. Acting promptly helps you stay compliant and avoid unnecessary stress or expense.