Key facts
- Acquisition cost: the purchase price plus stamp duty and legal fees on purchase.
- Enhancement expenditure: capital improvements that add value to the asset — but NOT maintenance or repairs.
- Incidental costs of disposal: estate agent fees, solicitor fees, valuation fees, advertising costs.
- Revenue expenditure (repairs, insurance, running costs) is not allowable for CGT — it may be deductible for Income Tax instead.
- If you received the asset as a gift, the market value at the date of the gift is your acquisition cost.
The Three Categories of Allowable Cost
The Taxation of Chargeable Gains Act 1992 (TCGA) allows three categories of expenditure to be deducted when computing a chargeable gain:[1]
- Acquisition cost (s.38(1)(a) TCGA) — the cost of acquiring the asset
- Enhancement expenditure (s.38(1)(b) TCGA) — capital expenditure that is reflected in the state of the asset at the time of disposal
- Incidental costs of disposal (s.38(1)(c) TCGA) — costs directly attributable to the disposal
1. Acquisition Cost
The acquisition cost is normally the price you paid for the asset, plus any directly related purchase costs:[1]
- Purchase price
- Stamp Duty Land Tax (SDLT) or Land Transaction Tax (LTT) on property
- Stamp duty or stamp duty reserve tax on shares
- Solicitor and conveyancer fees on purchase
- Survey or valuation fees at the time of purchase
- Estate agent fees (if you were the buyer)
- Auction house buyer’s premium
Special Acquisition Cost Rules
| Situation | Acquisition Cost |
|---|---|
| Purchased at arm’s length | Actual price paid plus related costs |
| Received as a gift | Market value at the date of the gift |
| Inherited | Probate value (market value at date of death) |
| Acquired from spouse/civil partner | Spouse’s original cost base (no gain no loss transfer) |
| Held on 31 March 1982 | Market value at 31 March 1982 (rebasing) |
| Created by the owner (e.g. a painting) | Cost of materials and any other direct expenditure |
2. Enhancement Expenditure
Enhancement expenditure is capital spending that adds to or improves the asset and is still reflected in its value at the time of disposal. It must be expenditure that was wholly and exclusively for the purpose of enhancing the asset’s value.[2]
What Counts as Enhancement
| Allowable (Enhancement) | Not Allowable (Maintenance/Repair) |
|---|---|
| Building an extension | Repairing a roof |
| Adding a new bathroom | Repainting walls |
| Converting a loft | Replacing broken windows with like-for-like |
| Installing central heating for the first time | Servicing an existing boiler |
| Adding a conservatory | Fixing a leaking gutter |
| Landscaping and hard-standing for parking | Mowing the lawn / general garden upkeep |
The “reflected in the state” test: The improvement must still be reflected in the asset at the time of sale. If you built an extension in 2010 but demolished it in 2020, the cost of the extension is not allowable because it is no longer reflected in the property’s state when sold.[2]
3. Incidental Costs of Disposal
These are costs you incur directly as a result of selling or disposing of the asset:[3]
- Estate agent or broker fees
- Solicitor and conveyancer fees
- Advertising the sale
- Professional valuation fees (where needed for the disposal)
- Stockbroker commission on share sales
- Auction fees
Similarly, incidental costs of acquisition are also deductible — they form part of the acquisition cost category.
What Is NOT Allowable
The following are common costs that are not deductible for CGT purposes:[1]
- Mortgage interest and other financing costs
- Insurance premiums on the asset
- Maintenance and repairs — keeping the asset in its existing state
- Rent, council tax, or utility bills
- Costs already deducted against Income Tax (e.g. rental property expenses claimed against rental income)
- Depreciation
- Your own time and labour (only professional costs paid to third parties are deductible)
No double-dipping: If you have already deducted a cost against Income Tax (for example, improvement costs claimed against rental income), you cannot deduct the same cost again for CGT purposes. Each cost can only be relieved once.[1]
Allowable Costs for Property Disposals
Property is the most common area where people need to identify allowable costs. A summary:[4]
| Cost | Allowable? | Notes |
|---|---|---|
| Purchase price | Yes | Or market value if gifted / inherited |
| SDLT on purchase | Yes | Part of acquisition cost |
| Solicitor fees (buy and sell) | Yes | Incidental costs |
| Estate agent fees on sale | Yes | Incidental costs of disposal |
| Extension or loft conversion | Yes | Enhancement expenditure |
| New kitchen / bathroom (upgrade) | Possibly | Only if a genuine improvement beyond the original |
| Roof repair | No | Maintenance / repair |
| Redecoration | No | Maintenance |
| Mortgage interest | No | Financing cost |
| Insurance | No | Running cost |
| Letting agent fees | No | Revenue expense (Income Tax deductible) |
Record-Keeping
You should keep records of all acquisition and enhancement expenditure for as long as you own the asset, plus the period within which HMRC can enquire into the disposal (typically six years from the end of the tax year). Records include:
- Purchase completion statements and contracts
- Receipts and invoices for improvement works
- Solicitor and estate agent invoices
- Stamp duty receipts
- Planning permission documents (may support the enhancement claim)
Frequently Asked Questions
What costs can I deduct from a capital gain?
You can deduct the original purchase price (or market value if gifted), stamp duty, legal fees on buying and selling, estate agent fees, enhancement expenditure (improvements, extensions), and professional valuation fees. You cannot deduct maintenance, repairs, insurance, or mortgage interest.
Can I deduct the cost of a new kitchen or bathroom?
It depends. If the new kitchen is a significant improvement beyond the original standard (e.g. adding a kitchen where there was none, or a substantially enhanced specification), it may count as enhancement expenditure. Simply replacing a worn-out kitchen with a similar one is maintenance/repair and not allowable.
Can I deduct mortgage interest from my capital gain?
No. Mortgage interest is a financing cost, not an allowable cost for CGT purposes. For rental properties, mortgage interest may provide Income Tax relief (as a basic-rate tax reduction for buy-to-let), but it cannot reduce the capital gain on sale.
What is my cost base if I inherited the asset?
If you inherited an asset, your acquisition cost for CGT purposes is the probate value — the market value at the date of death. You can also add any improvement expenditure and incidental costs you incurred after inheriting it.
Further Reading
- How to Calculate a Capital Gain — the full step-by-step computation
- Part Disposals — apportioning costs when you sell part of an asset
- CGT When You Sell a Rental Property — property-specific guidance
- Assets Acquired Before 1982 — rebasing rules for pre-1982 assets
Looking for simple tax software?
#GoFile is HMRC-recognised and trusted by 50,000+ UK businesses. Set up in minutes, file with confidence.
Get Started For FreeNo credit card required · Cancel anytime