Personal support for construction contractors
CIS monthly returns.You carry enough already.
Your people, your customers, the next job. There is a lot resting on your shoulders. Our CIS monthly returns service helps you stay on top of subcontractor checks, deductions and filing, with a clear plan and someone who listens.
No obligation. Tell us where you are, even if you are behind.
- Clear, agreed fees
- Approval before filing
- UK-wide remote support
A steadier month starts here
You should not have to figure it all out alone.
When the working day runs over, the paperwork often follows you home. We help turn the monthly CIS task into a routine you understand, with responsibilities agreed and questions answered.
Know what needs checking
We review the details needed for verification, deduction calculations and the return, and explain anything that needs your attention.
Keep the month organised
Agree a records deadline, a review process and who issues statements. You know what we need and what happens next.
Have a way forward
Missing returns or an HMRC letter? Start with a conversation. We identify the periods involved and agree a practical plan.
We support builders, developers, trade businesses and other contractors. CIS can apply to sole traders, partnerships and limited companies. Businesses outside construction can also become deemed contractors if their construction spending exceeds £3 million in a rolling 12-month period.
If you only receive CIS payments and need your own annual tax return, visit our CIS tax return service for subcontractors .
Get the foundations right
The right details before the first payment.
Your monthly CIS return, often called CIS300, reports payments to subcontractors within the scheme. It includes gross-status subcontractors as well as those paid after a deduction.
- Check the engagement. CIS registration does not prove someone is self-employed. The actual working arrangement matters.
- Verify when required. HMRC confirms the deduction rate or gross payment status. Returning subcontractors may need verification again if they were not on your returns in the current or previous two tax years.
- Keep the result. Use the correct identity, references and payment status, and act on relevant HMRC status-change notices.
Taking on your first subcontractor? Tell us before payment so we can review contractor registration and the information needed. Agency, umbrella and personal-service-company arrangements may require additional checks.
HMRC: subcontractor verification and employment status .
Three dates. Different responsibilities.
Your CIS monthly returns deadline, made clear.
A CIS tax month runs from the 6th of one month to the 5th of the next. Filing the return, giving subcontractors their statements and paying HMRC are separate tasks.
| Task | Deadline | Example: payments from 6 September to 5 October 2026 |
|---|---|---|
| File the CIS return | By the 19th after the tax month ends. | 19 October 2026. |
| Give deduction statements | Within 14 days of the tax month end where deductions were made. | 19 October 2026. |
| Pay deductions to HMRC | By the 22nd electronically, or the 19th if paying by post. | 22 October 2026 electronically; 19 October by post. |
Some contractors can pay HMRC quarterly if eligible, but CIS returns still need to be dealt with monthly. Allow time for your payment method and check weekend or bank-holiday arrangements. We agree a records cut-off that leaves time to review and approve the return.
HMRC: monthly filing , deduction statements and paying deductions .
The quiet months matter too
No subcontractor payments? Let us close the month properly.
From 6 April 2026, mainstream contractors must file a nil return for a month with no subcontractor payments, or notify HMRC of inactivity by the relevant deadline. A month with no deductions is different: payments to gross-status subcontractors still need reporting.
One month with no payments
A nil return tells HMRC there were no payments to report. Confirm the position with us, including any payments made outside your usual bookkeeping routine.
A longer pause in work
An inactivity request can cover up to six months. If payments restart, the relevant return must be filed; that ends the inactivity period. Tell us when plans change.
Deemed contractors have a different legal position. HMRC’s guide says they are not legally required to file nil returns, but notifying HMRC of a no-payment period helps prevent unnecessary penalty notices. We check the right treatment for your business.
HMRC: April 2026 changes , inactivity requests and CIS340, section 4.5 .
Know what the figures mean
A deduction your business can explain.
Use the rate HMRC provides. The calculation needs the correct gross payment, VAT treatment and eligible direct costs. A materials figure should reflect what the subcontractor actually paid, rather than an assumed percentage or a marked-up selling price.
| Step | Amount | What it means |
|---|---|---|
| Agreed payment | £1,500 | Labour and materials before the CIS deduction. |
| Direct materials cost | £300 | Evidenced cost paid directly by the subcontractor. |
| Amount subject to CIS | £1,200 | £1,500 less £300. |
| CIS deduction | £240 | 20% of £1,200. |
| Paid to subcontractor | £1,260 | £1,500 less the £240 deduction; the deduction is payable to HMRC. |
Illustration only: the subcontractor is not VAT registered and £300 is the actual direct materials cost, including any irrecoverable VAT. There are no other charges. Different VAT, plant-hire, expense or payment arrangements need their own calculation.
The construction VAT domestic reverse charge may apply to qualifying supplies between VAT-registered businesses. End-user status, the type of supply and other conditions matter. It changes how VAT is accounted for; it does not remove the CIS reporting task. We can discuss VAT support alongside your monthly CIS work.
HMRC: calculating CIS deductions and buying services under the VAT reverse charge .
CIS contractor records must normally be kept for at least three years after the end of the tax year they relate to. Other accounting or tax rules may require longer retention.
A checklist that earns its place
What we need for your monthly CIS return.
We agree a straightforward way to share records. You do not need to arrive with a perfect system; we will explain what needs organising.
- Subcontractor details: the correct name, business type and relevant tax or company references, shared through the agreed secure process.
- Verification records: HMRC references, rates and any status-change notices.
- Actual payments: dates and gross amounts, supported by invoices and bank or cash-payment records.
- Materials and VAT: direct-cost evidence, VAT details and relevant reverse-charge information.
- Changes and adjustments: retentions, advances, credit notes or unusual payment arrangements to review.
- Previous filing: earlier returns, statements and any HMRC correspondence when we take over.
We also agree how required payment and deduction statements will reach your subcontractors. These explain the payment and tax withheld; they are separate from the monthly return sent to HMRC.
HMRC: CIS contractor record keeping .
Connected records. The right reporting.
Online CIS filing and Making Tax Digital are different jobs.
Monthly CIS returns are submitted through HMRC’s CIS online service or suitable commercial CIS software. Making Tax Digital for Income Tax is a separate requirement for qualifying individuals. One submission does not replace the other.
CIS monthly returns
Report the relevant subcontractor payments and deductions for each CIS tax month.
Payroll and employer reporting
Employee payroll, RTI and any relevant Employer Payment Summary need their own treatment. We can agree payroll support alongside CIS.
MTD and annual tax
Qualifying sole traders may also need digital records, quarterly updates and an annual Income Tax return. See our MTD guidance for CIS businesses .
Does your company also suffer CIS deductions? Company recovery is handled through the appropriate PAYE/EPS process. Sole traders use a different route. We check both sides without simply netting figures off the contractor’s monthly return.
HMRC: CIS online filing , recovering deductions and MTD eligibility .
A service you can understand before you choose
Clear fees. Shared responsibilities. No guessing.
Your first chat is completely free. We look at the number of subcontractors, payment frequency, records and any earlier work, then provide a fixed-fee proposal for the support agreed.
What we agree to handle
- Verification support and deduction calculations within the agreed scope.
- Monthly return preparation, your approval and online submission.
- Preparation and delivery arrangements for deduction statements.
- Nil returns or inactivity requests when appropriate.
- Filing confirmation and a clear explanation of the amount and payment deadline.
What we agree with you
- The information cut-off and how records will be shared.
- Who confirms new subcontractors, working arrangements and actual payments.
- Who approves the figures and pays HMRC.
- The fee, any applicable VAT, software costs and volume limits.
- Any separate fee for catch-up work, corrections, enquiries or wider advice.
Tell us about your month
We listen to what is working, what is difficult and what is coming up.
Agree the routine
Set the scope, fee, records deadline and responsibilities together.
Review and approve
We explain the figures and queries before you authorise submission.
Know where you stand
Receive confirmation and the agreed statements and payment information.
If things have slipped
You can tell us the difficult bit first.
Unfiled returns, missing statements or an unexpected penalty can feel hard to face. You do not need to put everything right before asking for help.
Tell us which months are involved and share the relevant letters. We review what was filed, what was paid and what records are available, then agree the work needed to move forward.
A calm response to an approaching deadline
If a return is due soon, call us with the date. We will confirm what we can take on and what information is needed. Late filing and late payment have separate consequences.
Where an earlier return is wrong, the correction route depends on how it was filed. We check the original submission and software before making an amendment.
Communication is at the heart of what we do
You deserve an answer you can understand.
A question about a deduction should not sit at the back of your mind all day. We make space to explain the figures, discuss a change and agree the next step.
Keep in touch by phone or email, arrange a Teams or video meeting, or meet us at our Tattenhall office. Visits to your business can be discussed by arrangement. We agree what works around your working day.
3 Chowley Court, Chowley Oak, Tattenhall, CH3 9GA.
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The details contractors ask about
CIS monthly returns FAQs.
Do I report invoices or payments?
The monthly return should reflect payments and deductions in the relevant CIS tax month. An unpaid invoice does not become a reportable payment just because it was issued. Tell us about retentions, advances and set-offs so we can check their treatment.
Do gross-status subcontractors still go on the return?
Yes, payments within CIS still need to be reported even where the deduction is 0%. A nil return means no reportable payments, not simply no tax withheld.
What happens if a monthly CIS return is late?
The usual initial penalty is £100, followed by a further £200 at two months. At six months, a further penalty is normally the greater of £300 or 5% of the relevant CIS liability. A further penalty applies at 12 months, with higher amounts possible for deliberate withholding.
Special rules and reasonable-excuse appeals can affect the result. We review the notice and circumstances; we cannot promise cancellation. Late-payment interest and penalties are separate.
Can you fix a return filed by another accountant?
We can review it and agree any correction work. We need the original figures, evidence and filing method. A return submitted through commercial software cannot simply be amended using HMRC’s free service. Tell us who filed it and which system they used.
Does every building-related invoice fall within CIS?
No. The work, contract and parties matter. Some activities and payments are outside the scheme, and mixed contracts need care. We check the circumstances instead of deciding from the supplier’s job title alone.
From 6 April 2026, payments to qualifying local authorities and public bodies acting as subcontractors are outside CIS. This does not mean every payment by a public-sector customer is exempt.
Why do you ask questions about the labour supply chain?
From 6 April 2026, HMRC has additional powers where a business knew or should have known a relevant payment or CIS credit was connected with deliberate non-compliance. Consequences can include liabilities, penalties and loss of gross payment status.
Understanding who supplies the work and keeping appropriate checks is part of responsible administration. CIS verification alone is not a guarantee that the wider arrangement is correct.
Does appointing an accountant transfer my responsibilities?
You remain responsible for your business’s compliance. We make the work and responsibilities clear, including the information you provide, approval of figures and payment to HMRC. We use the appropriate agent-authorisation process; you should not share your HMRC password.
Can you work with our existing bookkeeper or payroll team?
Yes. We agree who maintains records, calculates deductions, issues statements, files each return and communicates payment amounts. Clear ownership helps prevent gaps or duplicate submissions.
What if we stop using subcontractors?
A temporary break may suit an inactivity request. If you stop using subcontractors permanently, HMRC must be told and the scheme position reviewed. Let us know before simply stopping the monthly process.
Can I use Swift just for monthly CIS support?
Tell us what is already covered by your current arrangements. We can discuss the CIS work you need and confirm whether a standalone service or a wider package is appropriate, with the scope and fee agreed before you proceed.
HMRC: late-return penalties , CIS340 guidance and the 2026 CIS fraud measures .
Support that fits the whole business
Keep the different parts connected.
For the life you are working hard to build
Let the working day end with a little less on your mind.
You do a lot for the people who rely on you. Let us start with one conversation about what would make your month easier.
Completely free to talk. No obligation to join. A clear proposal before any paid work begins.
