CIS Returns & Verification

Whether you're a contractor or subcontractor, our CIS accountant service keeps you compliant with the Construction Industry Scheme end to end, so deductions are correct and nothing gets missed.

What's included

  • Subcontractor verification with HMRC
  • Monthly CIS300 return filing
  • Reclaiming overpaid CIS deductions
  • CIS record-keeping & reconciliation

Who this is for

Contractors who need subcontractors verified correctly and a CIS300 return filed on time every month, whether or not anyone was paid that month. And subcontractors who want their deductions checked properly, registered at the right rate, and any overpayment actually reclaimed rather than left with HMRC.

If you're not sure whether you're registered correctly, or you suspect you've been overpaying, our plain-English guide to how CIS works and CIS deduction calculator are a good place to start. If you haven't registered yet at all, see our guide on how to register for CIS, and what happens if you don't.

How we handle it

We verify every subcontractor with HMRC before the first payment goes out, so the right deduction rate applies from day one, not corrected months later. Each month we prepare your CIS300 return from your actual payment records and file it ahead of the 19th deadline, whether or not anyone was paid that month, since a nil return is still required. Throughout the year we reconcile deductions suffered against your accounts, so when your tax return or company accounts are due, the CIS figures are already right rather than something to untangle at the last minute. If we spot that you're being overpaid at the wrong rate, we flag it straight away instead of waiting for year-end.

Not sure if your CIS is set up correctly?

Book a free discovery call and we'll check your registration, verification and returns are all in order.

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Frequently Asked Questions

What happens if I file my CIS return late?

HMRC charges an automatic £100 penalty the day after the deadline, rising to £200 after two months, then £300 or 5% of the CIS deductions shown on the return (whichever is higher) after six months, and again after twelve. We handle the monthly deadline for you so it doesn't come up.

Do I need to verify a subcontractor every time I use them?

Only if you haven't paid them within the current or previous two tax years, or HMRC specifically asks you to re-verify. We keep a record of who's already verified so you're not re-verifying unnecessarily.

I think I've been paying the wrong CIS rate — can that be corrected?

Yes. If a subcontractor was deducted at 30% when they should have been verified at 20%, or should have gross payment status, we identify the shortfall and factor it into their Self Assessment reclaim rather than leaving the money with HMRC.