CIS Returns

The Construction Industry Scheme is one of the most widely misunderstood parts of the UK tax system — and one of the most financially significant for those who operate within it. Introduced to address tax evasion in the construction sector, CIS requires contractors to deduct tax at source from payments made to subcontractors, at either the standard 20% rate (for registered subcontractors) or the higher 30% rate (for those not registered or not verified). For subcontractors, this means tax is effectively prepaid throughout the year against their annual liability. For contractors, it means a specific set of monthly filing obligations that carry automatic penalties when missed or incorrectly completed.

The most important thing for subcontractors to understand is that CIS deductions are not a final tax. They are deducted on account — credited against the tax liability that is calculated as part of the annual self assessment return. Once all legitimate business expenses are properly accounted for — tools and equipment, vehicle costs, materials, protective clothing, subcontractor payments made to others, and any other allowable costs — the actual tax owed is frequently lower than the total deductions made throughout the year. The difference is refundable by HMRC. Across Yorkshire, significant numbers of CIS subcontractors are entitled to substantial refunds that they have never claimed — simply because no one has ever walked them through the process. We calculate the full refund entitlement as part of every subcontractor self assessment return.

For contractors, the monthly CIS return is a compliance obligation with a hard deadline of the 19th of each month. Returns must be filed even in months where no payments were made to subcontractors — a nil return is still a required return. Subcontractors must be verified with HMRC before the first payment is made, and if the verification is not carried out the contractor must deduct at the higher 30% rate. Deduction statements must be issued to each subcontractor each month. Failing to meet any of these obligations attracts automatic penalties, and consistent non-compliance can trigger a CIS compliance review.

We work with CIS contractors and subcontractors across South Yorkshire and the wider Yorkshire region — including construction businesses in Barnsley, Rotherham, Doncaster, Sheffield, and beyond. CIS work almost always connects directly to self assessment for subcontractors, and our service covers both, so there is no gap between your monthly compliance and your annual return. If you are a subcontractor who has not filed self assessment for one or more years, or a contractor who has fallen behind on monthly returns, the free health check is the right and most efficient starting point.