CIS is a tax deduction system for construction subcontractors in the UK: the contractor deducts 20% (or 30% if you are not verified) from each payment. The real tax, taking into account Personal Allowance (£12,570) and expenses, is 3–4 times lower: with an income of £40,000 a typical refund is £3,500–6,000. You can get the overpaid amount back only through Self Assessment — free on gov.uk, deadline 31 January.
The contractor deducts 20% from each payment. But your real tax is 3–4 times lower. Self Assessment returns the difference. It is legal, free, and you can do it yourself.
Construction Industry Scheme (CIS) is an advance tax deduction system. The contractor (main contractor) deducts money from your payment and sends it to HMRC.
You are registered as a CIS subcontractor, the contractor verified you with HMRC using your UTR and name. This is normal.
The contractor could not verify your UTR with HMRC — for example, the name does not match, the UTR is wrong, or you are not registered. The losses are significant.
HMRC allows you to receive 100% of the payment without deductions. Requirements: 12+ months in business, a history of tax payments, turnover from £30,000.
According to CIS340 (HMRC guide) the contractor must: verify each subcontractor with HMRC before the first payment; issue a Monthly Payment and Deduction Statement within 14 days after the end of each tax month; submit a Monthly CIS Return to HMRC. This is not goodwill — it is the law.
From April 2026 HMRC has the right to revoke Gross Payment Status immediately if fraud is suspected in the supply chain. After revocation, GPS can be restored no earlier than 5 years later. If you have GPS — full compliance is mandatory.
CIS is deducted from gross income. Personal Allowance and expenses are not taken into account when the deduction is made. After SA the difference is returned.
With higher expenses (£8,000+) the refund exceeds £5,000. Builders with expenses of £10K+ regularly get £6,000+.
Every £1 of documented expenses reduces your taxable income. At the basic rate of 20% — that is £0.20 refund per £1. With £5,000 of expenses — +£1,000 to your refund. Keep all receipts.
Travel from site to site — 45p/mile (first 10,000 miles/year). Keep a mileage log: date, route, distance. This is one of the biggest sources of deductions for CIS.
HMRC test: «wholly and exclusively» for business. Any expense with a personal element must be split proportionally.
The CIS statement is your main proof of tax deducted. Without it HMRC cannot match your data with the contractor's data.
This is a breach of the law. Your steps:
HMRC requires you to keep all CIS statements for at least 5 years after filing SA. Take photos and store them in the cloud — paper copies get lost.
Without registration with HMRC the contractor applies 30% instead of 20%. Losses over a year are thousands of pounds.
gov.uk/register-for-self-employment (CWF1). Get a UTR (≈15 working days by post). Without a UTR the contractor cannot verify you.
Call the HMRC CIS helpline (0300 200 3210) or register online. You need a UTR, NI number, full name (exactly as in HMRC records).
The contractor verifies you with HMRC using your UTR + name before the first payment. Make sure the name matches — one wrong letter → 30%.
SA for your first year working as CIS. If you started in 2025/26 — submit by 31 January 2027.
HMRC verifies by name AND UTR. If the contractor enters «Alex» instead of «Alexander» or the wrong transliteration — verification fails and 30% applies. Use the name exactly as in HMRC records.
A CIS refund only comes through Self Assessment — not through P800 and not through Personal Tax Account. There is no other way.
P60, P45, CIS statements, банковские проценты, дивиденды, доход от аренды.
Если первая декларация — регистрация на gov.uk. ~15 рабочих дней по почте.
Заведите личный кабинет HMRC. Сохраните пароль офлайн — восстановление долгое.
Основная форма. Доходы, расходы, allowances. Online — проще, чем бумага.
SA103 для self-employed, SA105 для аренды, SA106 для иностранного дохода.
HMRC покажет итог: должны вы или вам. Сверьте с собственной таблицей.
Дедлайн online: 31 января. Бумажный: 31 октября. Штраф £100 за просрочку.
Enter GROSS income — the amount before CIS deductions, as shown in the statements. Not the net amount you received into your account.
All allowable business expenses with supporting documents. HMRC may ask for proof — you must have the receipts.
The EXACT amount from all CIS statements for the year. HMRC checks it against the contractor's data — a mismatch delays the refund.
Most delays are technical. They can be prevented.
The name in SA does not match the name in HMRC records (or the contractor's records). HMRC pauses processing for manual review.
You entered £5,000 CIS deductions, but the contractor reported £4,800. HMRC will ask for clarification. Only use numbers from official statements.
If you do not provide bank details for BACS — HMRC will send a cheque by post. This is much slower.
Some people enter the net amount (what they received) instead of gross. Then CIS deductions become a «double deduction» — SA gives an incorrect result.
HMRC does not publish fixed SLAs for CIS refunds. Actual times depend on HMRC's workload and the complexity of your claim.
Simple online SA with BACS — usually 4–8 weeks. Complex cases, paper SA, or if HMRC asks for additional documents — it can take several months. Do not call before 8 weeks after submission.
Check the status in your HMRC online account → Self Assessment → «View your SA calculation».
RIFT charges £354 fixed fee for CIS — it is not «free». On a refund of £3,000 that is 11.8%. Through SA yourself — £0.
HMRC возвращает одну и ту же сумму вне зависимости от посредника. Разница — только сколько посредник возьмёт себе.