PropCalc UK

UK residential capital gains tax was simplified in October 2024: 18% in the basic-rate band, 24% above. This calculator applies the correct band split against your other income, deducts the £3,000 annual exempt amount, and models PRR (Principal Private Residence) and Lettings Relief where they apply. Crucially, it also projects every future sale year to find the year of peak net proceeds — useful when capital growth assumptions favour holding but tax rates incentivise selling sooner.

May 2026 • 2026/27 tax year

Capital Gains Tax + Optimal Sale Year

UK residential CGT with the 18%/24% band split (post-Oct 2024 rates), £3,000 AEA, PRR + lettings reliefs — and an optimiser that projects every future year to find peak net proceeds.

My scenarios (0/10)

Save snapshots of your inputs to switch between scenarios (e.g. “65% LTV, higher-rate” vs “75% LTV, basic-rate”). Stored in your browser only — no login needed.

CGT today

Raw gain

£115,000

Reliefs (PRR + lettings + AEA)

£11,625

CGT owed

£24,810

Net proceeds

£325,190

Breakdown

Where the gain comes from and where it goes.

Optimal sale year

Best year (max net proceeds): year 10.

Lettings Relief — shared-occupancy only since April 2020. Most landlords no longer qualify. To claim, you must have lived in the property at the same time as the tenant (e.g. lodger arrangement) during the rented period. Don't tick the box just because you let the property out — HMRC will challenge.

Residential CGT must be reported and paid within 60 days of completion (UK-resident sales). Late interest base+2.5%, with 5% surcharges at 30d/6m/12m. PRR + lettings logic shown here is simplified — spousal transfers pre-sale, April 2015 rebasing for non-residents, and other edges are not modelled.

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Related guides

Plain-English explainers for the rules behind this calculator.

When to Sell a BTL: The Optimal Exit-Year Method

12 min read

Frequently asked questions

Answers to the questions UK property investors most often have about this tool and the underlying rules.

What is the CGT rate on residential property in 2026?
18% on gains falling in your remaining basic-rate band, 24% above. The £3,000 annual exempt amount applies. These rates have been unchanged since the October 2024 cut from 28% to 24%. Reporting and payment is required within 60 days of completion (UK residents).
Does PRR apply to my buy-to-let?
PRR applies only if the property was your main residence at some point. The exempt period is your actual occupation plus the final 9 months (regardless of occupation). For a property that was your home for 5 years then let for 10, PRR exempts (60 + 9) / 180 = 38.3% of the gain.
Does Lettings Relief still apply?
Only in shared-occupancy arrangements since April 2020. The pre-2020 form of Lettings Relief (which exempted up to £40,000 for any landlord with PRR history) was abolished. Today you must have been living in the property at the same time as the tenant for some period of the rental — a lodger arrangement, essentially. Most buy-to-let landlords do not qualify.
When do I have to report and pay residential CGT?
Within 60 days of completion (UK-resident disposals). Late submissions face interest at base rate + 2.5% (currently around 7-7.5%), plus a £100 fixed penalty after 30 days, more penalties at 6 and 12 months. Non-UK residents must report ALL residential disposals (including no-gain disposals) within 60 days.