Keep your CIS deductions, returns and tax records under control.
Practical UK accounting for builders and tradespeople. We help subcontractors check CIS deductions and claim repayments properly due, while helping contractors verify workers and meet monthly filing deadlines.
Built around how CIS builders and tradespeople actually get paid.
Self-employed subcontractors working under CIS — builders, plumbers, electricians, roofers, groundworkers and scaffolders
Contractors who take on subcontractors and need to verify them and file monthly CIS returns
Subcontractors having CIS tax deducted at source who want to claim back what they're owed
Tradespeople applying for or maintaining gross payment status
Anyone unsure whether they should be operating as a sole trader or limited company under CIS
The problems we see most
The same CIS headaches come up again and again.
CIS tax deducted from every invoice, but no one has ever reconciled it against what's actually owed
Contractor clients unsure how to verify subcontractors or file monthly CIS returns correctly
Tools, materials, and van costs claimed inconsistently, with no clear record of what's allowable
Uncertainty about whether CIS work is being set up in a way that protects genuine self-employed status
How the CIS review works
From unclear records to a practical filing plan.
01
Review the CIS position
We confirm whether you are acting as a contractor, subcontractor or both, then identify missing registrations, deduction statements, returns or records.
02
Fix the records and filings
We reconcile deductions, organise allowable costs and prepare the appropriate Self Assessment, payroll, VAT or monthly CIS work.
03
Keep the next deadline under control
You receive a clear document list and filing routine, with ongoing support available when monthly or quarterly work is needed.
Tailored CIS Support
Accounting built for the real challenges builders and tradespeople face.
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CIS Deduction Checks & Refund Claims
We match payment and deduction statements to your records, calculate the final tax position and claim any repayment properly due through the correct route.
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Monthly CIS Returns for Contractors
If you take on subcontractors, we verify them with HMRC and file your monthly CIS return on time, so you stay compliant and avoid late-filing penalties.
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Tools, Materials & Van Expenses
We help you correctly claim tools, materials, PPE, van running costs, and site-related expenses, so you're not overpaying tax on money you've already spent running your trade.
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Gross Payment Status Applications
If you meet HMRC's conditions, we help you prepare a gross payment status application so future payments can be received without CIS deductions.
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Employment Status Checks
We help you review working arrangements and identify status risks. CIS registration does not, by itself, prove that someone is genuinely self-employed.
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Direct Access to a Certified Accountant
No call centre queues or vague advice. Speak directly with a qualified UK accountant whenever you take on a new contract, buy equipment, or have a question about CIS.
Tax & MTD responsibilities
What HMRC expects from you under CIS.
Register as self-employed and for CIS with HMRC before starting subcontractor work
Have CIS tax deducted at source by contractors — 20% if verified, 30% if not — as an advance payment, not your final tax bill
File a Self Assessment return each year to reconcile CIS deductions against your actual Income Tax and Class 4 National Insurance
Register for VAT once your rolling 12-month turnover passes £90,000, and apply the VAT domestic reverse charge for construction services where it applies
Keep digital records and file quarterly under Making Tax Digital for Income Tax — mandatory from April 2026 for gross income over £50,000, and from April 2027 for income over £30,000
Contractors: verify every subcontractor with HMRC and submit monthly CIS returns by the 19th of each month
What to bring
Useful records for your first CIS review.
UTR and National Insurance number, or company details if you trade through a limited company
CIS payment and deduction statements received from contractors
Invoices, bank statements and details of any cash payments
Records for tools, materials, PPE, travel, van costs and other business expenses
Previous Self Assessment returns, CIS returns or HMRC correspondence where relevant
Supporting subcontractors and contractors across the trades:
General BuildingPlumbing & HeatingElectricalRoofingGroundworksScaffolding
CIS Accounting FAQs
CIS Accounting for Builders & Tradespeople — Common Questions
What is CIS and does it apply to me?
Under CIS, contractors normally deduct 20% from payments to registered subcontractors, 30% from unregistered subcontractors and 0% where HMRC confirms gross payment status. The scheme covers many construction activities, but CIS registration does not apply to employees and some work falls outside the scheme.
How do I claim back overpaid CIS tax?
For a sole trader or partner, CIS deductions are normally set against the final Income Tax and National Insurance position through Self Assessment. A repayment may arise when valid deductions exceed the final liability, but a refund is not automatic. Limited companies use a different PAYE-based claim process.
What expenses can builders and tradespeople claim?
Depending on the facts and your records, allowable costs may include tools, equipment, materials, PPE, insurance, accountancy fees and qualifying vehicle or travel costs. Private costs and ordinary commuting are not automatically allowable, so each claim needs to be checked.
I take on subcontractors — what do I need to do as a contractor under CIS?
You need to register as a contractor, verify each subcontractor with HMRC before paying them, deduct the correct CIS rate, and file a monthly CIS return by the 19th of each month. We can handle verification and filing for you so nothing is missed.
What is the VAT domestic reverse charge and does it affect me?
The domestic reverse charge applies to many standard- and reduced-rate construction services between UK VAT-registered businesses where the payment is reported under CIS. Exceptions include certain end users, intermediary suppliers and services outside the rules, so the supply chain needs to be checked before invoicing.
Does Making Tax Digital affect CIS subcontractors?
Yes, in the same way it affects other self-employed sole traders. From April 2026, subcontractors with gross income over £50,000 must keep digital records and submit quarterly updates to HMRC. That threshold drops to £30,000 from April 2027. We'll tell you when it applies and get your records ready in advance.
Not sure whether your CIS records and deductions are right?
Book a free CIS review. We will identify the records to check, the deadlines that apply and the most useful next step. Not ready to talk yet? Try our free CIS tax refund estimator to see roughly where you stand first.
