Running a construction business in the UK isn’t just about laying bricks or managing jobs—it’s also about managing your money. And one of the best ways to protect your profits is by understanding what expenses you can claim to reduce your tax bill.
In this article, we break down the key tax-deductible expenses for construction firms—whether you’re a one-man band or running a growing team.
What Are “Allowable Expenses”?
Allowable expenses are business costs you can deduct from your income before working out your tax. In short: they reduce the amount of profit you pay tax on.
But in construction, it can be tricky to know where the line is. Let’s make it simple.
Common Tax-Deductible Expenses for Construction Businesses
🛠️ Materials and Supplies
- Timber, bricks, plaster, paint, fittings, fixings—if you buy it for a job, it’s claimable.
- Even smaller consumables like nails, screws, and sealant count.
🚚 Tools and Equipment
- Hand tools, power tools, ladders, and machinery can usually be claimed.
- If you buy a large piece of equipment (like a cement mixer or digger), it may qualify for capital allowances.
🏗️ Protective Clothing and Uniforms
- High-vis jackets, steel-toe boots, hard hats, gloves, work trousers—anything required for safety on site.
- Everyday clothes (even if you only wear them for work) don’t usually count.
🚐 Vehicle Costs and Fuel
- If you use a van or car for business, you can claim:
- Mileage (if using the simplified flat rate method)
- Fuel, insurance, repairs, servicing (if using actual cost method)
- Only claim the business portion—keep a mileage log if the vehicle is also used personally.
🧾 Subcontractor Payments (CIS)
- Paying subcontractors? You can deduct their gross payments (before CIS deductions) as business expenses.
- Don’t forget to keep clear records for CIS reporting and verification checks.
🏢 Office and Admin Costs
- Phone and internet bills (business use portion)
- Business insurance
- Stationery and postage
- Software for quotes, invoicing, or project management (e.g., QuickBooks, Tradify)
📱 Mobile Phone
- You can claim the business percentage of your phone bill. If you have a separate business phone, even better.
🏠 Working from Home (Admin Work)
- If you use a home office for invoicing, chasing payments, or project planning, you can claim:
- A flat rate (HMRC’s simplified method)
- Or a percentage of household bills (if you have a dedicated space)
🧑🏫 Training and Courses
- Courses that help maintain or improve your existing skills are tax-deductible (e.g., health & safety, site management).
- Courses that teach new, unrelated skills usually aren’t.
💼 Accountancy and Professional Fees
- Fees paid to accountants, bookkeepers, legal professionals, or trade bodies like the FMB or CITB are all claimable.
What You Can’t Claim
Let’s clear up a few common misconceptions:
❌ Your own wages or salary (as a sole trader) – You’re taxed on profit, not pay
❌ Client entertaining – Meals and drinks with clients aren’t tax-deductible
❌ Fines and penalties – HMRC won’t reward late payment fees or speeding fines
❌ Everyday clothes – Unless it’s safety gear or branded uniform, clothing usually isn’t allowed
Bonus Tip: Keep Those Receipts!
HMRC may ask to see evidence of your expenses, so keep your:
- Receipts
- Invoices
- Bank statements
- Mileage records
You can go digital—apps like Dext, Xero, or even Dropbox help you store everything safely.
Conclusion: Keep More of What You Earn
Understanding what you can claim is one of the simplest ways to save tax and protect your profit. Whether you’re laying foundations or managing multiple sites, these tax tips will help you build a stronger business.
📞 Need help getting your expenses sorted?
We work with construction firms just like yours—so we know what counts and how to save you money.
Get in touch today for jargon-free, hands-on advice.
