When CIS Deductions Are Due: Monthly Deadlines Explained
Find out when CIS deductions are due to HMRC each month. Understand the 19th and 22nd deadlines, late payment penalties, and the quarterly payment option.
Key Actions
- Note the 19th (postal) or 22nd (electronic) monthly deadline for CIS payments to HMRC
- Set up a reminder for the 14th of each month to prepare your CIS return and payment
- Check whether you qualify for quarterly CIS payments instead of monthly
- Keep a record of all CIS deductions made and payments sent to HMRC
- File your CIS return by the 19th even if you made no subcontractor payments that month
CIS deductions are due to HMRC by the 19th of the month (postal payments) or the 22nd (electronic payments) following the end of each tax month. If you're a CIS contractor, you need to pay the deductions you've taken from subcontractor payments within this window. Missing these CIS payment deadlines triggers automatic penalties.
This guide explains the monthly CIS payment cycle, how tax months work, the penalty structure for late payments, and an alternative quarterly option for smaller contractors.
How the CIS Monthly Payment Cycle Works
The CIS payment cycle is based on tax months, not calendar months. A tax month runs from the 6th of one month to the 5th of the next.
| Tax month | Period | Payment deadline (postal) | Payment deadline (electronic) |
|---|---|---|---|
| Month 1 | 6 April – 5 May | 19 May | 22 May |
| Month 2 | 6 May – 5 June | 19 June | 22 June |
| Month 3 | 6 June – 5 July | 19 July | 22 July |
| Month 4 | 6 July – 5 August | 19 August | 22 August |
| Month 5 | 6 August – 5 September | 19 September | 22 September |
| Month 6 | 6 September – 5 October | 19 October | 22 October |
| Month 7 | 6 October – 5 November | 19 November | 22 November |
| Month 8 | 6 November – 5 December | 19 December | 22 December |
| Month 9 | 6 December – 5 January | 19 January | 22 January |
| Month 10 | 6 January – 5 February | 19 February | 22 February |
| Month 11 | 6 February – 5 March | 19 March | 22 March |
| Month 12 | 6 March – 5 April | 19 April | 22 April |
The rule: CIS deductions taken from subcontractor payments during a tax month are due to HMRC within 14 days of that month ending (19th), or 17 days for electronic payments (22nd).
CIS Payment Deadline: 19th vs 22nd of the Month
Your deadline depends on your payment method:
- 19th of the month — if you pay by cheque, at a bank, or by post
- 22nd of the month — if you pay electronically (online banking, BACS, Faster Payments, or through your HMRC online account)
Most contractors pay electronically, so the 22nd is the more common deadline. However, electronic payments need to clear HMRC's account by the 22nd — not just be initiated. Allow at least 2-3 working days for BACS transfers.
How Much CIS Tax to Pay HMRC Each Month
The amount you pay is the total CIS deductions taken from all subcontractor payments during that tax month.
Example: During the tax month 6 May to 5 June, a contractor pays three subcontractors:
| Subcontractor | Labour payment | CIS deduction (20%) |
|---|---|---|
| Sarah | £3,000 | £600 |
| James | £2,500 | £500 |
| Ben | £1,800 | £360 |
| Total due to HMRC | £1,460 |
The contractor pays £1,460 to HMRC by 19 June (postal) or 22 June (electronic).
If you also operate PAYE for employees, CIS deductions are typically paid alongside your PAYE tax and National Insurance using the same payment reference.
CIS Return Filing Deadline
The CIS return deadline is the same as the payment deadline — the 19th of the month following the end of the tax month. The return and the payment are separate obligations, but both fall due on the same date.
From April 2026, contractors are required to file a return every month — including nil returns when no subcontractor payments were made. Our guide on CIS monthly returns explains what the return contains and how it's filed.
CIS Late Payment and Filing Penalties
HMRC applies automatic penalties for late CIS returns, and interest charges for late payments.
Late Filing Penalties
| How late | Penalty |
|---|---|
| 1 day late | £100 |
| 2 months late | Additional £200 |
| 6 months late | Greater of £300 or 5% of the CIS deductions on the return |
| 12 months late | Greater of £300 or 5% of the deductions (higher for deliberate withholding) |
These penalties are per return. If you're late filing for three separate months, you receive three separate £100 penalties.
Late Payment Interest
HMRC charges interest on CIS deductions paid after the deadline. The late payment interest rate is 7.75% as of April 2026 (check the HMRC interest rates page for the current rate). Interest runs from the day after the deadline until the date HMRC receives payment.
Appealing Penalties
You can appeal a CIS penalty if you have a reasonable excuse for late filing or payment — for example, a serious illness, bereavement, or an HMRC system failure. Forgetting or being too busy is generally not accepted as a reasonable excuse.
Quarterly CIS Payments: An Alternative for Small Contractors
If your average monthly CIS deductions (combined with PAYE liabilities) are below £1,500 (2025/26), you may be able to pay quarterly instead of monthly.
Quarterly payment dates:
| Quarter | Period | Deadline (electronic) |
|---|---|---|
| Q1 | 6 April – 5 July | 22 July |
| Q2 | 6 July – 5 October | 22 October |
| Q3 | 6 October – 5 January | 22 January |
| Q4 | 6 January – 5 April | 22 April |
Important: Even if you pay quarterly, you still need to file your CIS return monthly by the 19th. The quarterly option only applies to payments, not to filing.
Contact HMRC to set up quarterly payments if your monthly amounts are consistently small.
CIS Deduction Deadlines: What Subcontractors Need to Know
As a subcontractor, you don't pay CIS deductions to HMRC yourself — your contractor does. But understanding the payment cycle helps you:
- Check your records — if your contractor pays HMRC late, the deductions may not appear on your HMRC record when you expect them
- File Self Assessment accurately — your CIS payment statements should match what HMRC received from your contractor
- Chase discrepancies — if your CIS deductions aren't showing in your HMRC online account, it may be because your contractor hasn't filed or paid yet
If your contractor's returns are late or missing, it can delay your CIS refund when you file Self Assessment.
Frequently Asked Questions
Do I pay CIS deductions separately from PAYE?
Generally not. If you run PAYE for employees alongside CIS, your CIS deductions are combined with your PAYE tax and National Insurance into a single payment to HMRC. You use the same Accounts Office reference number for both.
What if I didn't pay any subcontractors this month?
You still need to file a CIS return. From April 2026, nil returns are mandatory — you either file a nil return or pre-notify HMRC that no payments will be made. See our guide on CIS changes from April 2026 for details.
Can I get an extension on the CIS deadline?
No. The 19th/22nd deadline is fixed and cannot be extended. If you anticipate difficulty paying, contact HMRC before the deadline to discuss a Time to Pay arrangement rather than missing the deadline.
What if a subcontractor disputes the deduction amount?
The deduction rate is determined by HMRC during verification. If a subcontractor believes the wrong deduction rate was applied, they should check their registration status. As a contractor, you apply the rate HMRC tells you during verification and report it accurately on your return.
This guide is for informational purposes only and does not constitute tax, legal, or financial advice. Tax rules change frequently. Always verify current requirements on GOV.UK or consult a qualified accountant for your specific situation.