TAX • PROPERTY • 2025
Summary: This step-by-step guide explains how UK landlords must create a Capital Gains Tax on UK Property Account to report and pay CGT within 60 days of completion. It highlights the real penalties HMRC applies and how thousands of landlords fall foul of the rules each year.
- HMRC requires a 60-day CGT Return when you sell a UK residential property.
- You must create a dedicated “Capital Gains Tax on UK Property Account” — not your normal Government Gateway.
- Delays can trigger interest and penalties even if there is no tax due.
Why This Matters in 2025
ONS data shows over 940,000 UK residential property transactions in the latest rolling year. HMRC’s own figures indicate that thousands of landlords wrongly assume their Self Assessment tax return alone is enough. It isn’t — and HMRC has become far stricter.
Every UK landlord selling a buy-to-let must report the gain through the CGT on UK Property service if the property meets the conditions set out in HMRC’s reporting guidance. Even if the final CGT due is zero, the 60-day filing requirement still applies.
The Rules & Thresholds Every Landlord Needs to Know
For disposals on or after 6 April 2020, UK residents selling UK residential property must:
- File a CGT on UK Property Return within 60 days of completion.
- Pay estimated CGT within the same 60-day window.
- Use a dedicated “Capital Gains Tax on UK Property Account”.
- Report again via Self Assessment if required.
HMRC’s penalties for missing the 60-day deadline include late filing charges and interest, which apply even where HMRC processing delays slow down access to the online service — a frequent complaint raised by landlords.
| Requirement | What HMRC Expects | Deadline | Penalty Risk | Notes |
|---|---|---|---|---|
| Create CGT Property Account | Use Government Gateway but with a dedicated account | Immediately after exchange | Medium | Delays often caused by incorrect Gateway setup |
| Submit 60-Day Return | Online CGT reporting for residential property | 60 days post-completion | High | HMRC systems have no leniency for late reports |
| Pay Estimated CGT | Based on expected income for the full tax year | 60 days post-completion | High | Interest applies even if SA return later corrects figures |
Three Real Examples From UK Landlords
Example 1: Accidental Landlord Selling a Flat in Leeds
A landlord sold a former home turned rental property in Leeds. They assumed they could report via their Self Assessment return the following January. HMRC’s guidance proved otherwise. They filed 47 days late and received a penalty despite zero CGT being due due to PPR and letting relief.
Example 2: Portfolio Landlord Selling a Terraced House in Birmingham
This landlord used the wrong Government Gateway login created for PAYE, delaying CGT setup by a week. Because the return was then filed 18 days late, HMRC added interest despite the landlord arguing delays were caused by system confusion — a common issue Optimise sees.
Example 3: Landlord Exiting Buy-to-Let Due to Rising Costs
ONS reports indicate rising landlord exits as mortgage costs increased. One client selling a Nottingham property underestimated the CGT because they assumed their annual exempt amount was unchanged. The 2025 CGT personal allowance remains historically low, making early planning essential.
How to Create the CGT on UK Property Account
This is the most crucial step — and the one HMRC offers least clarity on.
Step 1: Sign in using the correct Government Gateway
You must use a personal Gateway login. Company Gateway IDs will not work. Follow HMRC’s official access page: https://www.gov.uk/report-and-pay-your-capital-gains-tax
Step 2: Create the dedicated “Capital Gains Tax on UK Property Account”
This is separate from your normal tax account. HMRC does not make this obvious and many landlords mistakenly assume they already have the right access. The correct pathway is explained in full here: Optimise guide to creating the account.
Step 3: Gather the required documents
- Completion statement
- Original purchase documents
- Costs of improvement (not repairs)
- Estate agent and legal fees
- Mortgage redemption fees (if applicable)
Step 4: Submit the 60-day return
Use HMRC’s online service and double-check:
- Your estimated taxable income for the year
- Correct private residence relief, if applicable
- Correct reporting date — HMRC uses completion, not exchange
Step 5: Pay the estimated Capital Gains Tax
HMRC expects “reasonable estimates”; later corrections occur via Self Assessment.
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Action List: What to Do Next
- Check if your sale triggers the 60-day rule
- Create the correct CGT Property Account
- Calculate estimated CGT early
- Use Optimise to review your figures
- Submit and pay before HMRC penalties apply
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Disclaimer: This article outlines general rules only. Individual tax outcomes differ based on personal circumstances. Seek professional advice.
Hashtags: CGT reporting, UK landlords, property taxes, HMRC penalties, capital gains
