Corporation Tax Payment: Deadlines, Methods & What Happens If You're Late
Filing your CT600 and paying your Corporation Tax are two separate deadlines. Many directors get caught out by this.
Key Deadlines
| Action | Deadline |
|---|---|
| Pay Corporation Tax | 9 months + 1 day after period end |
| File CT600 | 12 months after period end |
Example: Your accounting period ends 31 March 2025.
- Payment due: 1 January 2026
- CT600 filing due: 31 March 2026
The two deadlines are independent — you can file your CT600 at any point before the 12-month deadline, whether or not you have paid yet.
How to Pay
Bank Transfer (Faster Payments / BACS)
The fastest way. You need:
- Sort code: 08 32 10
- Account number: 12001039
- Reference: Your 17-character Corporation Tax payment reference
Your payment reference is a 17-character code: your 10-digit UTR + A001 + a 2-digit accounting period number (01 for your first period, 02 for your second, etc.) + A. For example, UTR 1234567890 for a first accounting period = 1234567890A00101A.
The safest way to get your exact reference is from the payslip HMRC sends you or by logging in to your HMRC online account. Using an incorrect reference means HMRC cannot match the payment to your account.
Direct Debit
Set up a direct debit through your HMRC online account. HMRC collects the payment on the due date.
Corporate Credit/Debit Card
Pay online via HMRC's payment portal. Note: Credit card payments incur a fee.
Cheque
Send to: HMRC, Direct, BX5 5BD. Include your payment reference. Allow 3 working days for delivery.
Quarterly Instalment Payments (QIPs)
Most small companies pay their Corporation Tax in one lump sum by the 9 months + 1 day deadline. However, if your company's annual taxable profits exceed £1,500,000 (divided by the number of associated companies plus one), you are classified as a "large company" and must pay in four quarterly instalments instead.
For a standard 12-month accounting period, the four instalments fall on:
| Instalment | Due Date |
|---|---|
| 1st | 6 months + 13 days after period start |
| 2nd | 9 months + 13 days after period start |
| 3rd | 13 days after period end |
| 4th | 3 months + 14 days after period end |
The first two instalments fall before your period ends — you need to estimate your profits. Companies whose profits first exceed the threshold in a period may have an extra year before QIPs begin.
What Happens If You Pay Late?
Interest
HMRC charges 7.75% per annum (from 9 January 2026) from the due date until payment. Interest accrues daily.
Example
You owe £10,000. You pay 3 months late.
Interest = £10,000 × 7.75% × (90/365) = approximately £191
Surcharges
Unlike filing penalties, there are no fixed surcharges for late Corporation Tax payments. HMRC charges interest only. However, persistent late payment can trigger:
- Collection proceedings (debt collectors)
- County court judgments (CCJs)
- Winding-up petitions (extreme cases)
Can't Afford to Pay?
Contact HMRC's Business Payment Support Service: 0300 200 3835
They can arrange a Time to Pay plan — typically 6-12 months to spread the payment. You'll still pay interest, but it prevents enforcement action.
Filing vs Payment: Don't Confuse Them
A common mistake: "I can't afford to pay, so I won't file." This is wrong — it means you get both late filing penalties AND late payment interest.
Always file on time, even if you can't pay yet. Then contact HMRC about payment.
Know how much you owe? File your CT600 with Taxpipe — £59. We calculate your exact Corporation Tax liability.