Capital Gains Tax has changed materially over the last several years. The annual exempt amount has been reduced in successive Finance Acts, rates and reliefs have been revised, and the procedural overlay for property disposals has been tightened through the 60-day reporting regime. For UK accountants, the cumulative effect is that CGT engagements are more frequent, more procedurally exacting, and more financially significant for clients than they were a few years ago.
This guide sets out where the CGT regime sits in 2026 from a practitioner's perspective. It covers the rates and allowance position, the 60-day property return, the principal reliefs, the rules on losses and connected parties, and the practical workflow that firms use to deliver CGT advice cleanly and at scale.
The headline rates and allowance
For 2026-27, the annual exempt amount sits at £3,000, having been reduced from £12,300 in the 2022-23 tax year through successive Finance Acts. The reduction has materially expanded the population of taxpayers who need to report and pay CGT, particularly individuals selling investment portfolios and second properties.
CGT rates remain banded by reference to the individual's income tax position. Standard-rate taxpayers face a lower CGT rate, while higher and additional rate taxpayers face the higher CGT rate. Residential property disposals attract a different rate set, with both the lower and higher rates above the equivalent rates for other assets. Trustees and personal representatives pay a single rate that applies to all chargeable gains.
The 60-day property return
Disposals of UK residential property that produce a chargeable gain must be reported to HMRC within 60 days of the completion date, with the CGT payment due at the same time. The regime applies to UK residents disposing of UK residential property and to non-UK residents disposing of any UK real estate.
The 60-day return is filed through HMRC's online service. The principal challenges in practice are: gathering acquisition cost information for properties acquired many years before disposal; computing private residence relief where the property has been used for mixed purposes; and handling the interaction with the self-assessment return at the end of the tax year, where any over- or underpayment is reconciled.
Principal reliefs
A number of reliefs continue to play a central role in CGT planning:
- Private Residence Relief, which exempts the gain on disposal of the taxpayer's only or main residence subject to the qualifying conditions
- Letting Relief, which provides limited relief on the disposal of a former main residence that has been let out, subject to the restrictions introduced in recent Finance Acts
- Business Asset Disposal Relief (formerly Entrepreneurs' Relief), which provides a reduced CGT rate on qualifying business disposals up to a lifetime limit of £1 million
- Investors' Relief, which provides a reduced CGT rate on qualifying investments in unlisted trading companies subject to detailed conditions and a separate lifetime limit
- Gift Hold-Over Relief, which defers gains on qualifying gifts of business assets
- Rollover and Reinvestment Reliefs for proceeds reinvested into qualifying business or EIS assets
Business Asset Disposal Relief in detail
BADR is the relief that most frequently arises in advisory work for trading company clients. To qualify, the disposal must be of qualifying assets - typically shares in the individual's personal company, securities, or the whole or part of a trading business carried on by the individual. The individual must have held the qualifying interest for at least the two years ending on the date of disposal, and the conditions around personal company status (5% shareholding, voting rights, and beneficial entitlement to distributions and assets on a winding up) must be satisfied throughout the qualifying period.
A common pitfall is the conversion of qualifying trading activity into non-qualifying investment activity in the run-up to disposal. Where significant cash balances accumulate, where the company adopts a substantial property investment activity, or where the trading group is restructured shortly before sale, BADR eligibility can be lost. Plan the disposal at least two years out wherever practicable.
Losses and the connected parties rules
Capital losses can be set against capital gains arising in the same tax year, with any unused balance carried forward indefinitely. Allowable losses must be claimed by notice to HMRC within four years of the end of the tax year in which the loss arose.
Disposals to connected parties (broadly, spouses, civil partners, certain relatives, and entities under common control) are treated as taking place at market value rather than at the actual consideration. Losses on disposals to connected parties can only be set against gains on disposals to the same connected party.
Acquisition cost and indexation
For individuals, the historic indexation allowance was abolished in 2008 and replaced by a single rebasing to market value at 31 March 1982 for assets held since that date. For companies, indexation continued in modified form before being frozen at December 2017 values.
Acquisition cost evidence is one of the most commonly missing elements in client files. For long-held assets, the firm may need to rely on the client's own records, third-party valuations, or contemporaneous documents such as solicitors' completion statements. Where evidence is genuinely unavailable, a reasoned estimate supported by available documentation is often the best the file can produce - but HMRC may question the estimate, and the client should understand that exposure before the disposal is signed off.
Interaction with self-assessment
For taxpayers required to file a self-assessment return, capital gains must be reported on the return in addition to any 60-day return that has already been filed for property disposals. The self-assessment return is the final reconciliation point, picking up any disposals not covered by the 60-day regime, applying losses and reliefs, and reconciling any over- or underpayment from the 60-day return.
A taxpayer who is not otherwise within self-assessment may be required to register where capital gains arise. The registration thresholds and timing requirements should be addressed at the disposal stage rather than left to the run-up to the 31 January self-assessment deadline.
Non-resident CGT
Non-UK residents are subject to CGT on disposals of UK land and property (residential and non-residential since April 2019) and on disposals of indirect interests in UK land via property-rich companies. Reporting is via the same 60-day return as for UK residents disposing of UK residential property, regardless of whether the non-resident is otherwise within UK self-assessment.
The interaction with double taxation treaties is fact-specific. In most cases the taxing rights over UK real estate sit with the UK under the relevant treaty, but the treaty position should be checked rather than assumed.
Common errors in practice
A handful of recurring errors account for most CGT remediation work. Acquisition cost is not properly evidenced. Private residence relief is claimed without supporting documentation of the period of occupation. Losses are not claimed within the four-year window and become unavailable. The 60-day return is missed because the client did not flag the disposal to the firm. And spouses' tax positions are not optimised through inter-spouse transfers before disposal.
A simple mitigation is to include CGT triggers in the firm's standard client communication. A short annual reminder that asks about anticipated disposals catches most of the missed-disposal cases before the 60-day clock starts running.
How Accupe supports CGT engagements
Accupe brings CGT advice into the same workflow as the rest of the firm's engagements. The AI document analyser reads completion statements, share registers, and historic acquisition documents with source citation. Smart Boards track CGT disposals through 60-day return preparation, partner review, and self-assessment reconciliation. The encrypted client portal handles secure exchange of valuation documents and identity evidence. Compliance Radar surfaces planning conversations alongside the rest of the client risk profile so that disposal-related advisory opportunities are not missed in the busy season.