Is a New Boiler Tax Deductible for Landlords? (2026)
Last updated 27 June 2026 · 7 min read · By the LandlordTaxAi Editorial Team
The short answer
Usually yes — as a repair. Replacing an old or broken boiler with a modern equivalent is normally an allowable revenue repair: you’re restoring the property, not improving it, and using today’s nearest equivalent doesn’t make it an improvement. But a significant upgrade — or installing heating where there was none — is likely capital, relieved against a future gain instead.
"Is a new boiler tax deductible?" is one of the most common landlord questions — and the answer turns on the repair-versus-improvement test. This guide explains why like-for-like replacement is a repair, when a boiler becomes capital, and what records support your claim.
See also repairs vs improvements and allowable expenses for landlords.
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Rental Profit Calculator
Add a like-for-like boiler replacement as a repair to see the effect on taxable profit.
Result
- Taxable profit (rent − expenses)
- £11,200
- Income Tax at 20%
- £2,240
- Less mortgage interest credit (20%)
- − £1,000
- Tax due on this property
- £1,240
- Income after tax
- £9,960
Like-for-like replacement is usually a revenue repair. A major upgrade may be capital. Estimate only.
Why like-for-like is a repair
HMRC accepts that replacing a worn or broken part with the nearest modern equivalent is a repair, not an improvement — even if the new boiler is more efficient simply because old models are no longer made. You’re restoring the property to working order, which is a revenue cost deductible against rental income.
A standard combi-for-combi swap because the old one failed is the textbook allowable repair.
When a boiler becomes capital
It tips into capital when the work goes beyond replacement and materially improves the property — for example installing central heating where there was none, or a substantially larger or higher-spec system that’s a genuine upgrade rather than a like-for-like swap. Capital costs aren’t deducted from rental income; they may reduce a future capital gain when you sell.
| Scenario | Likely treatment |
|---|---|
| Broken boiler replaced with similar model | Revenue repair (allowable) |
| Old boiler swapped for modern equivalent | Revenue repair (allowable) |
| First-ever central heating installed | Capital (CGT side) |
| Whole system upgraded to higher spec | Likely capital |
The question to ask: did I restore an existing asset (repair) or create a better one (improvement)? That answer drives the tax treatment.
Keep the right records
Keep the invoice describing the work, note that it replaced a worn or broken boiler, and keep any evidence (photos, engineer’s report). Clear documentation that you restored rather than improved the property is what supports a revenue claim if HMRC ever asks.
Repair or capital — recorded right
LandlordTaxAi reads your bank statements and helps categorise costs like a boiler replacement against the right HMRC category — keeping revenue repairs and capital items clearly separated.
See how it worksA worked example
A landlord replaces a failed boiler for £2,500 in 2026/27.
| Like-for-like replacement | £2,500 — allowable repair |
| Tax saved (basic-rate, 20%) | £500 |
| Tax saved (higher-rate, 40%) | £1,000 |
| If instead a first-time heating install | Capital — for CGT, not income |
As a repair, the full cost reduces rental profit; as a capital improvement, it would wait for the eventual sale.
Frequently asked questions
Is a new boiler tax deductible for landlords?
Usually yes as a repair if it replaces an old or broken boiler with a modern equivalent. A significant upgrade can be capital instead.
Why is like-for-like a repair?
Using the nearest modern equivalent doesn’t make a replacement an improvement — you’re restoring the property, which is a revenue repair.
When would a boiler be capital?
If you install heating where there was none, or a substantially larger/higher-spec system that improves the property.
Does replacing the entire system change things?
Replacing the boiler is usually a repair to the system; replacing the whole system as an upgrade is more likely capital.
What records should I keep?
The invoice describing the work, photos if useful, and a note that it replaced a worn/broken boiler.
How do I claim it under MTD?
If a repair, include it in allowable property expenses (repairs and maintenance) and record digitally. If capital, keep it for CGT records.
Written and reviewed by the LandlordTaxAi Editorial Team. Our guides are reviewed against current HMRC guidance and updated when the rules change. Operated by LandlordTaxAi, United Kingdom. Follow us on LinkedIn.
Last reviewed: 27 June 2026 · Researched against primary UK sources for the 2026/27 tax year: https://www.gov.uk/hmrc-internal-manuals/property-income-manual/pim2030; https://www.gov.uk/guidance/income-tax-when-you-rent-out-a-property-working-out-your-rental-income. This article is informational only and does not constitute tax advice. Check the latest details on GOV.UK or with a qualified accountant.