CIS returns for contractors and construction companies
If you pay subcontractors for building work, you are a contractor under CIS, the Construction Industry Scheme. That means checking each subbie with HMRC, taking the right tax off their pay, and a return every month. We run it for builders and building companies so you can get on with the job.
ACCA qualified accountants with over 20 years in practice
Your monthly CIS cycle
The tax month runs from the 6th to the 5th. Each one follows the same pattern.
Verify new subcontractors
Before you pay a new subbie, HMRC checks they are registered and tells you whether to take 20%, 30% or nothing. You verify again anyone you have not put on a return in the current or last 2 tax years.
Take the deduction from labour
The rate goes on the invoice after taking out VAT, materials the subbie paid for, plant hire, consumables and fuel (except for travel).
Send payment and deduction statements
Each subbie gets a statement within 14 days of the end of the tax month, showing what you paid and took off. They need these for their own CIS tax refund.
File the monthly return by the 19th
Your CIS return covers everyone you paid in the tax month and is due by the 19th of the month after it ends.
Pay HMRC by the 22nd
The deductions you took go to HMRC by the 22nd, or the 19th if you pay by post.
Nil returns are back
Since 6/4/2026 you must file a nil return for any month when you paid no subcontractors, unless you told HMRC in advance. So a quiet month between jobs still needs a return, and we file it for you.
Also from 6/4/2026, payments to local authorities and some public bodies are outside the scheme. If you do council work, we check how each payment should be treated.
Deadlines and penalties for contractors
Penalties start the day after the 19th and grow the longer a return is late.
| What | Rule or date | Source |
|---|---|---|
| Monthly return | By the 19th of the month after the tax month ends | GOV.UK (opens in a new tab) |
| Nil return | Must file a nil return, or tell HMRC in advance no payments will be made (rule in force from 6/4/2026) | legislation.gov.uk (opens in a new tab) |
| Payment to HMRC | By the 22nd of the month (19th if paying by post) | GOV.UK (opens in a new tab) |
| Late return penalty 1 day | £100 | GOV.UK (opens in a new tab) |
| Late return penalty 2 months | £200 | GOV.UK (opens in a new tab) |
| Late return penalty 6 months | £300 or 5% of the CIS deductions on the return (whichever is higher) | GOV.UK (opens in a new tab) |
| Late return penalty 12 months | £300 or 5% of the CIS deductions on the return (whichever is higher); later returns may get up to £3,000 or 100% of deductions | GOV.UK (opens in a new tab) |
| Wrong employment status declaration | Penalty up to £3,000 | GOV.UK (opens in a new tab) |
| Records | Keep at least 3 years after the end of the tax year; fine up to £3,000 if records cannot be shown | GOV.UK (opens in a new tab) |
Records, VAT and your own status
Keep your CIS records
Payments, deductions and verification details must be kept for at least 3 years after the end of the tax year, with a fine of up to £3,000 if you cannot show them. We keep them in order alongside your bookkeeping.
The VAT reverse charge
When a VAT registered subbie invoices you for CIS work, the domestic reverse charge usually applies and you account for their VAT on your own return.
VAT reverse charge for buildersEmployed or self employed?
Each return asks you to confirm your subbies are not employees, and a false declaration can bring a penalty of up to £3,000. If someone works like a member of staff, we talk it through with you before the return goes in.
How we run it for you
Send us who you paid
A photo of the invoices or a list each month, from your phone.
We verify, work out and file
New subbies verified, deductions checked, statements and the return sent before the 19th.
You pay HMRC
We tell you the amount due by the 22nd, and if you also run payroll with us, it all comes in one note.
Related services
The tax rules on this page come from GOV.UK and HMRC guidance. Last checked .
Questions about CIS for contractors
Am I a contractor under CIS?
If your business pays subcontractors for construction work, yes, even if you are also a subcontractor to someone else. We check what applies to you on a free call.
When is the CIS return due?
By the 19th of the month after each tax month ends. The tax month runs from the 6th to the 5th.
Do I need to file if I paid no subcontractors this month?
Yes, since 6/4/2026: file a nil return, or tell HMRC in advance that you will not be making payments.
What if HMRC cannot verify a subcontractor?
HMRC tells you which rate to use. A subcontractor who is not registered has 30% taken off instead of 20%.
What happens if a CIS return is late?
£100 straight away, £200 at 2 months, then £300 or 5% of the deductions on the return at 6 and 12 months, whichever is higher.
Let us run your CIS returns
Tell us how many subcontractors you pay and we will send you a quote. Or book a free call to ask questions first.