We are CIS accountants for UK construction subcontractors and contractors. The average CIS subcontractor overpays around £2,000 a year in tax deductions. We claim it back, then keep you compliant.
CIS deductions are taken before any expenses or allowances are applied. Most subcontractors overpay across the year. The refund is real money back in your pocket, and it starts with a correctly filed Self Assessment return.
Composite snapshots based on patterns across our CIS clients. Names and figures anonymised. The tax mechanics are real.
“Three years filing my own returns and I never got the materials split right. First year with a proper CIS accountant and the refund was more than four times what I had been getting.”
“My contractor was taking 20% off the full invoice including materials. Once we split it out correctly and claimed the mileage, the refund was considerably larger than expected.”
“Applied for GPS on the advice of our accountant. No more 20% taken every month. The cash flow difference on a £500k-a-year turnover is enormous.”
The 20% CIS deduction is taken before any expenses or allowances are considered. Materials, mileage, tools, PPE and van costs are never factored in at source. Most subcontractors are owed a meaningful refund at year end, but only if someone files the Self Assessment return correctly.
CIS deductions apply to labour only. The cost of materials you supply is excluded. Many main contractors apply the 20% to the full invoice value rather than splitting out materials. When that happens you overpay on every single job and the difference is recoverable.
Limited company subcontractors can reclaim CIS deductions in real time via the EPS process, rather than waiting for the annual Self Assessment return. At higher income levels the cash flow difference is significant. We model both structures for your situation.
GPS means no CIS deduction at all. You receive the full payment and settle the tax yourself. To qualify you must pass three tests and, from April 2026, maintain strict due diligence to avoid immediate revocation. We handle the application and keep you compliant.
Every service is built around how CIS works in practice, not generic small-business accounting.
We calculate the full refund you are owed, account for all allowable expenses, and submit your Self Assessment return. Most subcontractors receive their refund within 8 to 12 weeks.
GPS eliminates the 20% deduction entirely. We manage the application, the three qualifying tests, and the ongoing compliance that keeps GPS active under the April 2026 rules.
Annual Self Assessment filed correctly, with every allowable expense claimed. No missed mileage, no unclaimed tools, no overpayment left on the table.
EPS real-time reclaim of CIS deductions, Corporation Tax, annual accounts and Companies House filings for CIS-registered limited companies.
Monthly CIS300 returns filed on time. From April 2026, nil returns are mandatory for months with no subcontractor payments. We handle every filing, including nil returns.
VAT domestic reverse charge advice, MTD ITSA preparation, and a full review of allowable expenses: mileage at 55p per mile (from April 2026), tools, PPE and van costs.
CIS works the same way across trades, but the materials split, expenses and typical refund size differ by trade. We know the specifics.
The materials split, the mileage rate, GPS qualification tests, April 2026 nil returns, EPS real-time reclaims: these are things a generalist accountant handles occasionally. We deal with them every week across a large CIS client base.
| Area | Our approach |
|---|---|
| CIS deduction base | Labour only, materials excluded (we verify every deduction slip) |
| Self Assessment refund | All allowable expenses included, filed to maximise refund |
| GPS application | Three-test assessment, application handled, compliance maintained |
| EPS real-time reclaim (Ltd Co) | CIS suffered offset against PAYE/CIS liabilities each month |
| Mileage (from April 2026) | 55p per mile (first 10,000), 25p thereafter |
| April 2026 nil returns | Filed for every inactive month, penalties avoided |
| MTD ITSA | £50k gross income threshold from April 2026 (not net) |
The deduction base, GPS qualification, April 2026 nil returns, EPS real-time reclaims. We see these issues every week, so we know where the refunds and risks are.
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UK based, UK regulated, serving British construction businesses and the trades that build the country.
Book a free call. We will review your CIS deductions, identify what you are owed, and explain your options. No hard sell, no obligation.
Plain English articles on CIS deductions, refunds, gross payment status, VAT reverse charge and MTD. Written by specialist CIS accountants.