If you work in the UK construction industry — whether as a contractor, subcontractor, or business owner — you have likely come across the term CIS payroll. Understanding how the Construction Industry Scheme (CIS) works is essential for staying compliant with HMRC regulations, avoiding penalties, and managing your cash flow effectively. In this comprehensive guide, we will explain everything you need to know about CIS payroll, how it operates, who it applies to, and what your responsibilities are under the scheme.
What Is the Construction Industry Scheme (CIS)?
The Construction Industry Scheme (CIS) is a set of special tax rules introduced by HM Revenue & Customs (HMRC) that governs how payments are made between contractors and subcontractors in the UK construction industry. The scheme was designed to reduce tax evasion in the construction sector, which historically had high levels of tax non-compliance due to the transient and project-based nature of construction work.
Under CIS, contractors are required to deduct money from their subcontractors’ payments and pass these deductions directly to HMRC. These deductions count as advance payments towards the subcontractor’s tax and National Insurance contributions. Essentially, instead of subcontractors receiving their gross payment and being solely responsible for paying their tax at the end of the year, the contractor withholds a portion and pays it directly to HMRC on their behalf.
The CIS applies to a wide variety of construction activities, including:
- Site preparation and foundation work
- Demolition and dismantling
- Building and construction work
- Alterations, repairs, and decorating
- Installing systems such as heating, lighting, power, water, and ventilation
- Cleaning buildings after construction work
It is important to note that certain activities are excluded from CIS, such as architecture and surveying, scaffolding hire (without labour), carpet fitting, and the manufacture of materials used in construction.
Who Does CIS Apply To?
CIS applies to two main groups of people: contractors and subcontractors.
Contractors
A contractor under CIS is a business or individual who pays subcontractors for construction work. This includes:
- Construction companies and building firms
- Property developers
- Government departments and local authorities
- Any business that spends more than £1 million per year on construction in any three-year period (even if construction is not their main business)
Subcontractors
A subcontractor is anyone who carries out construction work for a contractor. Subcontractors can be:
- Sole traders
- Partnerships
- Limited companies
Both contractors and subcontractors must register with HMRC under CIS before they begin working under the scheme. While subcontractor registration is not legally mandatory, failing to register means they will face higher deduction rates on their payments.
How Does CIS Payroll Work?
CIS payroll differs from standard payroll in several important ways. Here is a step-by-step breakdown of how the process works:
Step 1: Registration
Before any payments are made, both contractors and subcontractors should register with HMRC for CIS. Contractors must register before taking on any subcontractors. Subcontractors who are already registered for Self Assessment can register for CIS through HMRC’s online services or by calling the CIS helpline.
Step 2: Verification of Subcontractors
Before making the first payment to a new subcontractor, the contractor must verify the subcontractor with HMRC. This verification process tells the contractor what deduction rate to apply:
- 0% (Gross payment status) — Subcontractors who meet HMRC’s criteria can receive gross payments, meaning no deductions are taken. This is typically available to subcontractors with a good tax compliance history and a certain level of turnover.
- 20% (Standard rate) — Applied to subcontractors who are registered for CIS but not approved for gross payment status.
- 30% (Higher rate) — Applied to subcontractors who are not registered with HMRC for CIS, or whose details cannot be verified.
Step 3: Making Payments and Applying Deductions
When a contractor pays a subcontractor, they must calculate the correct deduction. Importantly, the deduction only applies to the labour element of the payment — not to the cost of materials. For example, if a subcontractor’s invoice totals £2,000, with £1,200 for labour and £800 for materials, the deduction is only calculated on the £1,200 labour portion.
Using the standard 20% rate, the contractor would deduct £240 (20% of £1,200) and pay the subcontractor £1,760, while forwarding the £240 to HMRC.
Step 4: Providing Payment and Deduction Statements
After making a payment, the contractor must provide the subcontractor with a CIS payment and deduction statement. This document must include:
- The contractor’s name and registration number
- The subcontractor’s name and verification number
- The gross amount paid
- The cost of any materials included
- The deduction amount taken
Subcontractors rely on these statements to reconcile their tax records and claim back overpaid tax through their Self Assessment tax return.
Step 5: Monthly Returns to HMRC
Contractors are required to submit a monthly CIS return to HMRC by the 19th of each month (or 22nd if paying electronically). This return details all payments made to subcontractors in the previous tax month and the deductions made. Even if no payments were made in a given month, a nil return may still be required.
Failure to submit returns on time or inaccurately can result in significant penalties, starting at £100 for one day late and increasing the longer the return remains outstanding.
What Are Gross Payment Status and Its Benefits?
As mentioned earlier, subcontractors with gross payment status receive their full payment without any deductions being taken. This is highly beneficial for cash flow, as subcontractors receive more money upfront rather than waiting to reclaim it through their tax return.
To qualify for gross payment status, subcontractors must meet three tests set by HMRC:
- Business test— They must be carrying on a business in the UK related to construction.
- Turnover test— They must have net construction turnover of at least £30,000 per year (for sole traders) or £30,000 per director (for companies).
- Compliance test— They must have a satisfactory tax record, with no outstanding returns or significant tax debts.
HMRC reviews gross payment status annually, and it can be removed if a subcontractor fails to meet compliance requirements.
CIS Payroll vs Standard PAYE Payroll
It is important to understand the distinction between CIS payroll and standard PAYE payroll. Under PAYE, employers deduct income tax and National Insurance contributions from employees’ salaries. Under CIS, deductions are made from subcontractors’ payments, but subcontractors are not employees — they are self-employed or operating as limited companies.
This means that subcontractors are responsible for their own National Insurance contributions and tax returns, while contractors are only responsible for deducting CIS amounts and reporting them to HMRC. However, it is worth noting that HMRC may investigate whether workers are genuinely self-employed or are actually employees, a distinction with significant tax and legal implications — often referred to as the issue of employment status.
Common Mistakes to Avoid Under CIS
Many contractors and subcontractors make avoidable errors that lead to penalties and compliance issues. Here are some of the most common mistakes:
- Failing to verify subcontractors before making the first payment
- Applying deductions to the full invoice amount rather than just the labour component
- Missing monthly CIS return deadlines, even when no payments have been made
- Failing to keep accurate records of payments, deductions, and verification details
- Not providing deduction statements to subcontractors
- Incorrectly classifying workers as subcontractors when they should be employees
Staying on top of these responsibilities is crucial, especially as HMRC can conduct compliance checks and audits at any time.
Reclaiming CIS Deductions
For subcontractors, CIS deductions are essentially tax paid in advance. At the end of the tax year, subcontractors declare their income through a Self Assessment tax return and offset the CIS deductions made throughout the year against their overall tax liability. If deductions exceed the tax owed, HMRC will issue a refund.
For limited company subcontractors, CIS deductions can be offset against PAYE liabilities and other tax obligations. In some cases, companies may need to apply to HMRC for a repayment if their CIS deductions exceed their total PAYE and National Insurance liability.
Record-Keeping Requirements Under CIS
Both contractors and subcontractors have a legal obligation to maintain accurate records related to CIS. Contractors should retain:
- Records of all subcontractors verified and the results
- Copies of all monthly returns submitted to HMRC
- Payment records and deduction statements issued
- Details of all gross payments made
Subcontractors should keep all deduction statements received, invoices issued, and records of materials costs. These records should be retained for a minimum of three years after the end of the tax year to which they relate.
Do You Need Professional Help With CIS?
Managing CIS payroll can be complex and time-consuming, particularly for businesses juggling multiple subcontractors, varying deduction rates, and monthly reporting obligations. Even a small administrative error can result in costly penalties from HMRC. Many contractors and subcontractors choose to work with experienced accountants to manage their CIS obligations efficiently, ensuring full compliance while freeing up time to focus on the actual business of building.
Work With Mac&G Accounting — Your Trusted London Accountants
If you are self-employed, a sole trader, or a limited company operating in the construction industry in London, navigating Self Assessment and CIS obligations can feel overwhelming. That is where Mac&G Accounting comes in.
Based in London, Mac&G Accounting is a professional accounting and bookkeeping firm with extensive experience supporting individuals and businesses across a wide range of industries — including construction. Whether you need help completing your Self Assessment tax return, managing your CIS deductions, understanding your gross payment status, or keeping your financial records accurate and up to date, Mac&G Accounting has the expertise and dedication to guide you every step of the way.
We understand that no two clients are the same. Our team takes a personalised approach to every client relationship, offering tailored advice and practical solutions that reflect your unique financial situation. We stay up to date with the latest HMRC regulations so that you do not have to — giving you peace of mind and complete confidence that your tax affairs are in safe hands.
If you are based in London and looking for reliable, professional, and affordable accounting and bookkeeping services, we warmly invite you to get in touch with Mac&G Accounting today. Let us take the stress out of Self Assessment and CIS compliance so that you can focus on what you do best. Contact our friendly team to arrange a consultation and discover how we can support your financial success.
Managing your tax obligations under the Construction Industry Scheme does not have to be complicated. With the right professional support, you can stay compliant, protect your cash flow, and build a stronger financial future — one project at a time.
