HMRC updates CIS nil returns starting 6 April 2026

If you run a site or handle the books for a contractor, two practical Construction Industry Scheme changes land on 6 April 2026. First, if you make no subcontractor payments in a tax month, you’ll usually have to file a ‘nil return’. Second, some payments to specified public bodies will sit outside CIS. Both are set out by HMRC in draft regulations published on GOV.UK and scheduled to commence on that date. (gov.uk)

Quick refresher so we’re learning from the same page: CIS is the UK system where contractors deduct money from subcontractors’ pay and send it to HMRC. It’s designed to make sure tax is collected across the supply chain, including for firms based outside the UK doing construction work here. (gov.uk)

Here’s the monthly rhythm you work to. A tax month runs from the 6th to the 5th. Your CIS monthly return for that period is due with HMRC by the 19th of the following month. Keeping that simple timeline in mind will make the April changes easier to apply. HMRC’s internal manual spells this out. (gov.uk)

What’s changing on returns: HMRC’s draft regulations re‑state that when you’ve previously made contract payments but make none in a given tax month, you must still submit a return showing no payments. The deadline is 14 days after the end of that tax month. There’s a single exception: if you told HMRC at least 14 days before the start of that tax month that you wouldn’t be making any payments, you don’t need to file a nil return for that month. Think of it as two clocks-14 days before the start to opt out, 14 days after the end to file if you didn’t. (gov.uk)

Let’s turn that into dates you can use. Suppose you expect no subcontractor payments in the tax month running 6 May to 5 June 2026. To avoid filing a nil return, you must notify HMRC by 22 April 2026-14 days before 6 May. If you don’t notify, you’ll need to file a nil return by 19 June 2026-14 days after 5 June. This follows the legal wording on the two 14‑day rules and HMRC’s standard ‘due by the 19th’ timetable. (gov.uk)

The second tweak removes some public‑sector admin. A new provision confirms that a payment under a construction contract is not a CIS ‘contract payment’ if it’s made to a person in section 59(1)(b) to (k) of the Finance Act 2004-bodies that include certain public authorities. In practice, where your project structure involves paying such bodies, CIS deductions and reporting won’t apply to those payments. HMRC’s explanatory note and manual material provide the context. Always check who your counterparty actually is before switching off CIS. (gov.uk)

Who’s affected and how much: this directly affects contractors within section 59(1)(a)-that’s businesses whose activities include construction operations. If you’re a smaller contractor with quiet months, expect more consistent filing unless you use the pre‑notification route. If you work on public projects and your contracts involve payments to listed public bodies, expect fewer CIS line items to reconcile for those specific flows. (gov.uk)

A quick “what this means” box in words. For planners: build a standing diary entry a fortnight before each new tax month to decide whether to pre‑notify inactivity. For record‑keepers: treat nil months like any other return-file by the usual 19th unless you’ve already told HMRC not to expect one. For reviewers: update your internal CIS checklist so the ‘two 14‑day rules’ are visible to everyone who approves returns. The GOV.UK consultation summary frames these changes as administrative simplification. (gov.uk)

Penalties still bite if you miss a return. HMRC’s factsheet says there’s an initial £100 penalty the day after the deadline, £200 at two months, and further penalties at six and twelve months-£300 or 5% of the liability, with higher amounts for deliberate failures. Even if there’s no liability on a nil month, the fixed penalties can still apply unless HMRC accepts a reasonable excuse. Don’t let a quiet month become an expensive one. (gov.uk)

How to put this into practice from April. Use your HMRC CIS online account or software to tell HMRC about months with no payments; historically you could mark a scheme ‘inactive’ from the 6th, but from 6 April 2026 you’ll need to pre‑notify inactivity at least 14 days before the month starts if you want to avoid filing a nil return. Keep a simple log showing the date you notified HMRC and the month it covers-future you will thank you. (gov.uk)

Learning takeaways for students and early‑career pros: this is a live example of secondary legislation tweaking the admin, not the tax rates. The change is precise, date‑bound, and relies on definitions in primary law (Finance Act 2004). When you read a rule, always look for the clock, the exception, and the definitions. Here, the clocks are the two 14‑day rules; the exception is pre‑notification; the definitions sit in section 59. (gov.uk)