FREE TOOL · 2024/25 TAX YEAR
Find out how much of your CIS tax deductions you can get back. Enter your earnings, expenses and deduction rate — we'll calculate your estimated refund in seconds.
Auto-calculated as 20% of your earnings (£5,600). Override if your CIS statements show a different total.
Estimated Refund
£2,449
Based on your earnings, expenses and CIS deductions — HMRC likely owes you money.
Register for Self Assessment — if you haven't already, register at gov.uk before 5 October following the tax year.
Collect your CIS statements — ask each contractor for a CIS payment and deduction statement for every month you worked under CIS.
Gather your expense receipts — tools, fuel, PPE, insurance, phone. The more legitimate expenses you can evidence, the smaller your tax liability.
File by 31 January — online Self Assessment returns for 2024/25 must be filed by 31 January 2026. File early to get your refund faster.
This is an estimate only. Figures depend on your exact expenses, other income sources, and individual circumstances. Class 2 NI, personal allowance changes, and other deductions may affect your actual liability. Consult a qualified accountant or tax adviser to calculate your actual CIS refund.
The Construction Industry Scheme (CIS) requires contractors to deduct tax at source from subcontractor payments. Here's what that means for your take-home pay and tax return.
When a contractor pays you, they deduct 20% (or 30% if you're unverified) from the labour element of your invoice and pay it directly to HMRC. You receive the net amount — the deducted tax is essentially an advance payment on your Self Assessment bill.
The tax you actually owe is based on your profit, not your gross earnings. Claiming all legitimate expenses reduces your taxable profit and therefore your tax liability — which is why most CIS subcontractors end up with a refund.
Your annual Self Assessment return compares what was deducted under CIS against what you actually owe. If CIS deductions exceed your liability, HMRC refunds the difference. If they fall short, you pay the balance by 31 January.
The 20% CIS rate often exceeds the effective tax rate once expenses and the personal allowance are factored in. Someone earning £28,000 with £4,000 of expenses has a taxable profit of £24,000 — giving an actual tax and NI bill well below the £5,600 deducted at source.
Everything you need to know about CIS tax refunds.
You claim a CIS refund by filing a Self Assessment tax return with HMRC. Include all your CIS deductions on the return — your contractor(s) should give you CIS payment and deduction statements each month. Once HMRC processes your return (submitted online by 31 January each year), any overpaid tax is refunded directly to your bank account, usually within 5–10 working days of the return being accepted. If you've never filed Self Assessment before, you'll need to register first at gov.uk — do this well before October 5th in the tax year after you started working under CIS.
You can claim any expense that is wholly and exclusively for your trade. Common allowable expenses include: tools and equipment (including replacement and small purchases); van or vehicle costs (fuel, insurance, servicing, MOT) or mileage at 45p/mile for the first 10,000 miles; PPE — gloves, boots, hard hat, hi-vis; mobile phone (business proportion); materials you supply directly to jobs; public liability and other business insurance; training and certifications directly related to your trade; accounting and professional fees. You cannot claim everyday clothing, personal meals, or commuting to a regular fixed workplace. Keep all receipts — HMRC can ask for evidence.
Once you submit your Self Assessment tax return online, HMRC typically processes it and issues the refund within 5–10 working days, provided everything is in order. If you file on paper it can take 4–6 weeks longer. The vast majority of CIS refunds are issued within 2–4 weeks of the online submission being accepted. Occasionally HMRC puts a return into manual review, which can extend this to 8–12 weeks. To avoid delays: file online rather than by post, use the exact figures from your CIS statements, and ensure your bank details in your HMRC account are up to date.
Standard CIS deduction is 20% for verified subcontractors — those whose details HMRC has confirmed to the contractor. If a subcontractor cannot be verified (e.g. they haven't registered with HMRC, haven't filed previous tax returns, or gave incorrect details), the contractor must deduct at the higher rate of 30%. In either case, the deducted amount is paid directly to HMRC as an advance against your tax bill. If the 30% rate has been applied all year, your refund will typically be larger because the deductions almost certainly exceed your actual liability. If you're on 30% deduction, register with HMRC as a CIS subcontractor as soon as possible to get back on the standard 20% rate.
Estimate income tax and NI for sole traders for any earnings level.
Find out what to charge per hour based on trade, experience and region.
Calculate your HMRC mileage allowance and annual vehicle expense claim.
See your true margin on every job after labour, materials and overheads.
Calculate total labour cost for a job including NI and travel.
Download 10 free blank PDF invoice templates for UK tradesmen.
GET MORE BACK
Better expense records mean a bigger refund. Sleepless Tradesman tracks your jobs, mileage and materials automatically — so nothing slips through come January.
No card · No commitment · Cancel anytime