CIS Tax Refund - subcontractor tax specialists

Paid under CIS? You're probably owed a tax refund.

Contractors deduct 20–30% of your pay before you ever see it — but that flat deduction ignores your £12,570 tax-free allowance and every expense you're entitled to claim. We file your return, claim your refund and charge one transparent fixed fee, agreed before any work starts — then keep you compliant all year now Making Tax Digital is here.

Estimate my refund — free, no sign-up How it works
20–30% deducted from CIS pay at source
£1,500+ typical refund for full-time subbies
4 years of past refunds still claimable
Illustration of a construction subcontractor holding a tax refund cheque

CIS tax refund calculator

Move the sliders to match your year and see your estimated refund instantly. Unlike other refund sites, we don't ask for your name, phone number or email to show you the number — the whole calculation happens on your device and nothing you enter is sent anywhere or stored.

Your labour income — the gross amount on your CIS statements before the deduction.
Tools, PPE, van & fuel, insurance, phone… see the full list.
CIS deduction rate on your payslips
🔒 Calculated on your device — nothing sent or saved

Your estimated CIS tax refund

£0

Taxable profit (income − expenses)£0
Income tax due (2026/27)£0
Class 4 National Insurance£0
Total you actually owe£0
CIS tax already deducted£0

Estimate only, using 2026/27 rates for England, Wales & Northern Ireland (Scottish income tax bands differ). Assumes CIS work is your only income and standard personal allowance. Your actual refund depends on your full circumstances — this is not tax advice. Full disclaimer.

Why do CIS subcontractors overpay tax?

The Construction Industry Scheme takes a flat 20% (or 30% if you're not registered) off every payment, from the first pound you earn. But the tax system doesn't work like that:

  • Your first £12,570 is tax-free (the personal allowance) — CIS deductions ignore it.
  • Your expenses reduce your taxable profit — tools, PPE, van costs, insurance — CIS deductions ignore those too.
  • Tax is only ever due on profit, not turnover.

Put those together and the flat deduction almost always overshoots. The difference is your money — and HMRC will only give it back if a self assessment tax return is filed to claim it. That's what we do.

It can go the other way, though. The 20% roughly covers basic-rate income tax, but it doesn't cover National Insurance — and if your profits reach the 40% band, or you have other income alongside CIS work (a PAYE job, rent, pensions), or student loan repayments, the deductions can fall short. That's why our calculator tells you honestly when you'd owe more rather than pretending everyone gets a cheque — and why it's worth knowing your position early either way.

Subcontractor on site wearing a tool belt with hammer - tools and equipment are allowable expenses
Tools, equipment and consumables are allowable expenses.

How your claim works

Three steps, most of them ours. You could be done in ten minutes.

1

Send us your paperwork

CIS statements or payslips, and a note of your expenses. Photos on your phone are fine — we'll tell you exactly what we need and chase anything missing.

2

We prepare & you approve

A qualified accountant prepares your self assessment return, claims every expense you're entitled to, and shows you the refund figure before anything is filed. No surprises.

3

HMRC pays your refund

We file, HMRC processes — typically 2–8 weeks — and your refund lands in your own bank account, direct from HMRC. We never handle your refund money.

Expenses you can claim as a CIS subcontractor

Every pound of allowable expenses is a pound less profit to be taxed — which means a bigger refund. These are the ones we check on every claim:

  • Tools and equipment (including repairs and hire)
  • Protective clothing and PPE — boots, hi-vis, gloves, helmets
  • Van or car costs for work travel — fuel, insurance, repairs, or mileage
  • Travel and parking between sites
  • Materials you bought yourself for jobs
  • Public liability insurance
  • Phone and internet (the work-use share)
  • Accountancy and bookkeeping fees
  • Union or trade body subscriptions
  • Training courses that update existing skills
  • Working-from-home allowance for admin
  • Bank charges on a business account

Read the full CIS expenses guide

Not another refund factory

HMRC has cracked down hard on high-volume "repayment agents" — percentage fees, refunds paid into the agent's bank account, sign-ups that assign them your legal rights. We're an accountancy practice, and we think you deserve better:

Typical refund company CISTaxRefund
Fee Often 20–36% of your refund One fixed fee, agreed up front
Estimate before sign-up Enter your phone number first Instant calculator, no details asked
Where your refund goes Agent's account, then forwarded (minus fees) Your bank account, direct from HMRC
Who does the work Processing centre A CIMA-regulated accountancy practice
Your data Marketing lists, tracking cookies No tracking, no cookies, no lists
After the refund Gone until next year Year-round Making Tax Digital filing & support

The refund is just the start — Making Tax Digital is here

Making Tax Digital for Income Tax (MTD) is now law for the self-employed. If your qualifying income is over £50,000 — that's your gross turnover before CIS deductions, not your profit — you're already required to keep digital records and send HMRC quarterly updates. Over £30,000 joins from April 2027, and over £20,000 from April 2028. That means five HMRC deadlines a year instead of one.

Digital records, sorted

We set you up on MTD-compatible record-keeping that suits how you actually work — photos of receipts and CIS statements from your phone, not spreadsheet homework.

Every quarterly update filed

Four quarterly submissions a year, done for you, on time, with your CIS deductions tracked as you go — so there are no surprises and no penalties.

Year-end & your refund

The final declaration wraps up your year and claims back what you're owed. Because we've kept the records all year, it's faster — and your refund estimate is visible months in advance.

Ask about year-round MTD support

CIS tax refund FAQs

Straight answers to the questions subcontractors actually ask.

What is a CIS tax refund?
Under the Construction Industry Scheme (CIS), contractors deduct 20% (or 30% if you're unregistered) from your pay and send it to HMRC as an advance payment of your tax. Because that flat deduction ignores your tax-free personal allowance (£12,570) and your work expenses, most subcontractors have overpaid by the end of the tax year. The overpayment comes back to you as a refund once a self assessment tax return is filed.
How much will my refund be?
It depends on your income, expenses and deduction rate — refunds of £1,500–£3,000 are common for full-time subcontractors. The calculator above gives you an instant estimate without asking for any personal details.
Why might I not get a refund?
The 20% CIS deduction roughly matches basic-rate income tax, but it doesn't account for Class 4 National Insurance (6% of profits above £12,570), so NIC always eats into the headroom your allowance and expenses create. Deductions can fall short altogether if your profits reach the 40% higher-rate band (above roughly £50,270), if you have other income alongside CIS work — a PAYE job, rental income, pensions or dividends — or if you make student loan repayments or owe the Child Benefit charge. A tax return is still legally required either way, and knowing the position early means no January surprises. We'll tell you the honest number before anything is filed.
How long does a CIS refund take?
Once your return is filed, HMRC typically pays refunds within 2–8 weeks. Filing soon after the tax year ends on 5 April usually means a faster turnaround — it's worth getting your paperwork in early.
Do I have to file a tax return if I'm paid under CIS?
Yes — self-employed subcontractors must register for self assessment and file every year (online deadline: 31 January following the end of the tax year). For most subbies the return produces a refund rather than a bill, so it pays for itself.
Can I claim for previous years?
Usually up to four tax years back. If you've never claimed, or missed a year, there may be several refunds waiting — we check every open year as part of one claim.
What paperwork do I need?
Ideally your CIS statements (payment & deduction statements) from each contractor, plus receipts or records for expenses. Missing statements aren't fatal — bank statements and our checks can usually reconstruct the picture.
I'm on the 30% rate — can you help?
Yes. The 30% rate means you're not CIS-registered, so you're overpaying even more. We can register you for CIS (dropping future deductions to 20%) and claim back the excess you've already paid.
Does Making Tax Digital affect me as a CIS subcontractor?
Quite possibly. Making Tax Digital for Income Tax requires the self-employed to keep digital records and send HMRC quarterly updates — it already applies if your qualifying income (gross turnover before CIS deductions) is over £50,000, with the £30,000 band joining from April 2027 and £20,000 from April 2028. That's five deadlines a year instead of one. We handle the whole cycle — records, quarterly updates and the year-end declaration that claims your refund.
Is my refund guaranteed?
No honest firm can guarantee a refund — it depends on your real figures, and anyone promising a number before seeing them should worry you. What we do promise: we review your figures and agree the fee with you before any work starts, and if the numbers say a claim isn't worthwhile we'll tell you straight rather than filing for the sake of a fee.

Start your claim

Tell us a little about your situation and we'll come back within one working day with exactly what we need and a confirmed fixed fee — no obligation.

Email: enquiries@cistaxrefund.co.uk

Phone: 0121 550 5700 (Mon–Fri, 9am–5pm)

CISTaxRefund is a trading name of Blythe Phillips, an accountancy practice regulated by the Chartered Institute of Management Accountants (CIMA). Your information is used only to handle your enquiry — see our privacy policy.