A short story with three practical CGT lessons for your 2024/25 Self Assessment

Sarah runs a small design studio in Manchester. In summer 2024 she sold a plot of land she’d held for years. It wasn’t her home, so there was no private residence relief. “Easy,” she thought. “I’ll put it on my tax return in January and move on.”

By October, two things had happened:

she’d reinvested part of the proceeds, and
she’d stumbled across conflicting guidance online about capital gains tax (CGT) rates.

When she finally rang me in December, the problem wasn’t the gain itself — it was how and when to report and which rate to use. She was days away from making three avoidable mistakes.

Here’s how we fixed it — and what you can learn for your own 2024/25 return.

Lesson 1 — First, decide if you actually need to file (and register in time)
Sarah hadn’t clocked that she must report gains for 2024/25 if any of the following apply:

Chargeable gains before losses exceed the Annual Exempt Amount (AEA) of £3,000.
Total disposal proceeds exceed £50,000, even if the net gain is small.
She wants to claim a CGT relief (other than private residence relief).
She wants to claim a capital loss (losses must be claimed with computations within 4 years of the tax year end).

Because the AEA has fallen sharply, more people like Sarah fall into Self Assessment than they expect. If you’re not already in SA and any of the above apply, register, file, and pay for 2024/25 by 31 January 2026.

Bonus route: Sarah could have used HMRC’s real-time CGT service to report during the year and avoid SA entirely if she had no other SA reason — but only if the gain wasn’t from UK residential property. The deadline to use real-time for 2024/25 gains is 31 December 2025.

Property twist: If you dispose of UK residential property, there’s a separate 60-day reporting and payment obligation. UK residents don’t need to 60-day report only where there’s no CGT to pay. And note: with a narrow exception (set out in ICAEW guidance), 60-day reporting does not replace putting the gain on your SA return.

Lesson 2 — Make sure you’re using the correct CGT rate for 2024/25
Sarah’s second trap was rates. From 30 October 2024, the main CGT rates for assets other than residential property and carried interest changed during the tax year:

Basic-rate band: 10% → 18%
Higher-rate: 20% → 24%

Because the change landed mid-year, some software (and SA’s default calculations) may not apply the new rates correctly. If your SA calculation doesn’t reflect the right rate, you should adjust box 51 to get the correct liability. HMRC provides an online calculator you can use to check the figure before you file.

We reviewed Sarah’s income bands, applied the revised rate to the portion of her gains that fell after the effective date, and corrected her return accordingly.

Lesson 3 — Choose the right reporting route at the right time
Sarah assumed “January” was the only deadline. In fact, your path depends on what you sold and what else you need to report:

No other SA reason + non-residential gain? Consider HMRC real-time CGT by 31 December 2025 to avoid registering for SA.
UK residential property? Think 60-day report and payment within 60 days of completion. Then include in SA unless the narrow exception applies.
Already in SA or other reasons to file? Include gains/losses on your 2024/25 SA by 31 January 2026.

A note on cryptoassets (the easy box to miss)
Crypto isn’t cash for tax. For CGT, tokens are pooled like shares. Exchanging one token for another, or spending crypto on goods/services, can be disposals.

For 2024/25, the SA CGT pages include new dedicated boxes (13.1–31.8) for crypto. Don’t skip them. If you claim losses or have multiple wallets/exchanges, pull proper computations together — and claim losses within four years.

Looking ahead, the Cryptoasset Reporting Framework (CARF) arrives in the UK from 1 January 2026. HMRC will receive much more third-party data, and the measure is expected to raise ~£315m by 2029/30 — a clear signal that under-reporting is on HMRC’s radar.

How Vectigalis Tax helps (without the drama)
At Vectigalis Tax, we turn the “what do I file, when, and at what rate?” headache into a checklist:

Gatekeeper test — Do you need SA, real-time CGT, and/or 60-day?
Rate integrity — We test the 30 Oct 2024 change
Losses & reliefs — Capture and claim within time limits.
Crypto — Reconcile pools and complete the new SA boxes properly.
Payment planning — No late-payment interest, no avoidable penalties.

If Sarah’s story feels familiar, get ahead of it now — long before January.

If you sold land, shares or crypto in 2024/25 and want the right route, rate and deadlines (including the 30 Oct rate change), let’s get it correct now—well before January.

Contact Angelo Chirulli at angelo@vectigalistax.co.uk or visit vectigalistax.co.uk to arrange a focused consultation.

Mr Angelo Chirulli

ACA ADIT BFP TEP CPA (Ita)

This post is for general information only and isn’t tax advice. Facts matter. If you’d like a precise position for 2024/25 (including property and crypto), contact us and we’ll review your numbers and deadlines.