Structures and Buildings Allowance: The 3% Relief Businesses Forget to Claim (2026)
The Structures and Buildings Allowance gives businesses a straight-line 3% annual deduction on qualifying commercial construction costs, but it's widely under-claimed. Here's exactly how it works.
Why SBA was introduced
Before October 2018, there was no capital allowance at all available for the cost of constructing or renovating a commercial building's basic structure and shell — allowances were only available for plant, machinery, and certain integral features within it. The Structures and Buildings Allowance closed this long-standing gap, giving businesses a modest but real ongoing deduction for the structural cost of qualifying non-residential buildings.
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Unlike many capital allowances that use a reducing-balance method (a larger deduction in earlier years, tapering off over time), SBA uses a straight-line 3% rate, meaning the deduction is identical every year until the qualifying expenditure is fully relieved.
| Feature | Detail |
|---|---|
| Annual rate | 3% of qualifying cost |
| Method | Straight-line (equal amount every year) |
| Full write-off period | Approximately 33.3 years |
Worked example
A business incurs £600,000 of qualifying construction costs on a new warehouse.
| Year | Annual SBA claim |
|---|---|
| Year 1 | £18,000 (3% of £600,000) |
| Year 2 | £18,000 |
| ... | £18,000 each year |
| Year 33 (final, partial) | Remaining balance |
Over approximately 33 years, the full £600,000 is relieved at a steady £18,000 per year, rather than a larger deduction concentrated in the early years.
What qualifies — and what doesn't
| Item | SBA eligible? |
|---|---|
| Commercial office building construction cost | Yes |
| Warehouse or factory construction | Yes |
| Hotel or serviced office structure | Yes |
| Cost of the land itself | No — never eligible |
| Residential property (houses, flats used as dwellings) | No — explicitly excluded |
| Integral features (heating, lifts, electrical systems) | No — claimed under separate capital allowances rules instead |
| Fitted plant and machinery within the building | No — claimed under separate capital allowances (potentially with Annual Investment Allowance) |
SBA and residential property: the key exclusion
A critical limitation is that SBA does not apply to residential property. This means:
| Property type | SBA available? |
|---|---|
| Office building | Yes |
| Retail unit | Yes |
| Buy-to-let residential flat | No |
| Furnished holiday letting (residential) | No |
| Care home (varies — check current guidance on qualifying use) | Case-by-case, depending on the specific use and structure |
Landlords and property investors focused on residential lettings should not expect to claim SBA on their portfolio, which is a common point of confusion given how frequently SBA is discussed alongside other landlord tax reliefs.
The mandatory allowance statement
To claim SBA, the business incurring the qualifying expenditure must prepare an allowance statement, recording:
- Details identifying the structure or building.
- The date the structure was first brought into non-residential qualifying use.
- The total qualifying construction costs.
Interaction with a property sale
When a qualifying building is sold, the remaining, unclaimed SBA balance transfers to the new owner, who continues claiming the same 3% straight-line rate for the remainder of the original 33.3-year period (not a fresh 33.3-year period from their own purchase date). This is why the allowance statement is essential documentation in commercial property transactions — without it, a purchaser has no way to establish or continue the SBA claim.
Why SBA remains widely under-claimed
Despite being available since October 2018, SBA remains under-claimed, particularly by:
- Smaller businesses unaware the relief exists at all, especially if their accountant hasn't specifically flagged eligible construction spend.
- Property buyers who didn't request or receive the allowance statement from the seller, losing access to an otherwise valid ongoing claim.
- Businesses that conflate SBA with other capital allowances, assuming their structural spend is already covered elsewhere, when in fact it requires its own, separate SBA claim.
Use our corporation tax calculator and self-employed tax calculator to model the impact of an annual 3% SBA deduction on your business's ongoing tax position.
Frequently asked questions
What rate is the Structures and Buildings Allowance given at?
3% per year on a straight-line basis, meaning qualifying construction costs are written off evenly over approximately 33.3 years, rather than a reducing-balance or accelerated method.
What does the Structures and Buildings Allowance actually cover?
It covers the construction, renovation, or conversion costs of non-residential structures and buildings, including most commercial buildings, offices, warehouses, hotels, and similar structures, but explicitly excludes residential property, and excludes the cost of the land itself.
Does SBA replace other capital allowances like the Annual Investment Allowance?
No. SBA specifically covers the structure and shell of a building — the parts not otherwise eligible for other capital allowances, such as walls, roofs and foundations. Integral features, plant and machinery within the building (heating systems, lifts, fitted kitchens in commercial premises) are still claimed separately under the normal capital allowances regime, including the Annual Investment Allowance where applicable.
Do I need specific documentation to claim SBA?
Yes. You need an 'allowance statement' recording the qualifying costs, the date the structure was first used, and other prescribed details. Without this statement, the allowance cannot be claimed or transferred to a subsequent purchaser of the property.
Can SBA be claimed by a sole trader or only limited companies?
Both. SBA is available to any business — sole trader, partnership, or limited company — incurring qualifying construction expenditure on a non-residential structure used for a qualifying business purpose.
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