Construction Industry Scheme (CIS) Accountants in London

For Contractors

• 🔹 CIS registration, verification & monthly returns (CIS300) — stay compliant and avoid penalties.
• 🔹 Accurate deduction calculations — apply correct rates and materials rules so you don’t over- or under-deduct.
• 🔹 HMRC submissions + payment/deduction statements — neat records and audit-ready paperwork.
• 🔹 Employment status support — avoid status risks; manage enquiries and penalty appeals.
• 🔹 Onboarding & offboarding subs — verification checks, rate set-up, statements, and year-end packs.
• 🔹 Payroll & CIS coordination — align payroll cycles with CIS deductions to smooth cash flow.

For Subcontractors

• 🔹 CIS registration & gross payment status applications — reduce or remove deductions where eligible.
• 🔹 Payment reviews & reclaiming over-deducted CIS — faster tax refunds; tidy evidence.
• 🔹 Self-Assessment returns — include CIS suffered correctly so you get back what you’re owed.
• 🔹 Guidance on CIS rules + cash-flow optimisation — invoice layout, materials vs labour, and record-keeping.
• 🔹 Support with HMRC queries — we talk to HMRC so you don’t have to.

Main Contractors

Builders and project leads paying multiple subcontractors every month.

Subcontractors

Electricians, plumbers, joiners, decorators, trades on day-rates or fixed jobs.

Owner-Managed SMEs

Firms that need CIS aligned with bookkeeping, VAT, payroll, and year-end.

Fast-Growing Teams

Scaling crews needing better processes, documentation, and HMRC readiness.

1) Diagnose

We review invoices, statements, ledgers, and HMRC history.

2) Prepare

Fix set-up, verify subs, and align materials/labour split.

3) File

Submit CIS300 on time, issue statements, and maintain records.

4) Support

Deal with HMRC queries and keep everything audit-ready.

Penalty-Proof Filing

On-time CIS300 returns and tidy statements.

Cash Flow Clarity

Correct deductions; no nasty surprises.

Faster Refunds

We reclaim over-deducted CIS quickly.

HMRC Peace of Mind

We deal with HMRC so you can get back to work.

Do subcontractors have to register for CIS?

Yes. If you carry out construction work in the UK, you should register for CIS. If you don’t, contractors will deduct tax at a higher rate.

What is a CIS300 and when is it due?

CIS300 is the monthly return contractors submit to HMRC listing payments and deductions for each subcontractor. It is due by the 19th of the following month.

How do I reclaim over-deducted CIS tax?

Sole traders usually reclaim through Self-Assessment; limited companies reclaim through their PAYE/CIS account. We reconcile statements and submit the claim with evidence.

What’s “materials” vs “labour” for CIS?

Materials and certain eligible plant hire are excluded from CIS deductions. Correctly separating materials from labour ensures the right deduction is taken.

Should I apply for gross payment status?

If you meet HMRC compliance and turnover tests, gross status can help cash flow by removing deductions at source. We assess and apply where appropriate.

What records do I need to keep?

Invoices, deduction statements, verification numbers, materials evidence, and payment dates. We provide a simple checklist so your records are audit-ready.

What if a contractor deducted the wrong rate?

We check verification and paperwork, correct through statements and future submissions, or recover via your tax return, depending on the case.

How long do CIS refunds take?

Timings vary by route and HMRC workload. With complete evidence, Self-Assessment refunds can be processed in weeks; PAYE/CIS reclaims for companies may take longer.