CGT Calculator — UK Capital Gains Tax
UK Capital Gains Tax calculator
Estimate your Capital Gains Tax in seconds — based on the 2026/27 rules and the £3,000 annual exempt amount. Indicative only: private residence relief, BADR, holdover, gifts to spouses and other reliefs can change the answer materially.
Work out your CGT
2026/27 rates: 18% on residential gains within basic rate band, 24% above. Other assets: same 18%/24% from 30 Oct 2024.
How CGT works
Capital Gains Tax is charged on the profit when you sell or give away an asset that has gone up in value. It applies to second properties, shares outside an ISA or pension, business sales, valuable possessions and certain personal items. Your main home is usually exempt under Private Residence Relief.
The two big numbers to know: your annual exempt amount of £3,000 for 2026/27 (cut from £12,300 a few years ago, so it bites much harder now), and the rate, which depends on whether you are a basic-rate or higher-rate taxpayer once the gain is added to your income.
- Basic-rate taxpayer (income + gain still within £50,270): 18% on the gain
- Higher / additional rate (above £50,270): 24% on the gain
- BADR (Business Asset Disposal Relief): 18% from April 2026 — covers up to £1m of qualifying lifetime business gains
For UK residential property the gain must also be reported and the tax paid within 60 days of completion via HMRC’s online CGT-on-property service.
Frequently asked questions
Is my main home subject to CGT?
Usually no — Private Residence Relief covers the period it was your only or main residence, plus the final 9 months. If you let it out for periods, or used a portion exclusively for business, part of the gain may be taxable.
What allowable costs can I deduct?
The original purchase cost, legal and survey fees on purchase and sale, estate agent fees, stamp duty paid on purchase, and the cost of capital improvements (extensions, kitchens, new roofs). General maintenance and repairs are not allowable.
Can I transfer assets to my spouse to use both annual exemptions?
Yes. Transfers between spouses or civil partners are made on a no-gain-no-loss basis, so each of you can use a £3,000 annual exempt amount. This is one of the most under-used CGT planning moves.
What is the 60-day rule for property?
If you sell a UK residential property at a gain (not your main home), you must report it and pay an estimated CGT bill within 60 days of completion. The final position is then settled on your self-assessment return. We can do the 60-day return for clients.
Are CGT rates likely to change?
Rates can change in any Budget. The October 2024 Budget aligned non-residential rates with residential rates (both 18%/24%) and the BADR rate is on a phased rise. Always check the current rate when planning a disposal.
Want this looked at properly?
The calculator is a starting point. Once you factor in private residence relief, BADR, gifts, holdover or losses brought forward, the actual answer can be very different. We can run the proper numbers and prepare your CGT return.