When Should You Pay Corporation Tax to HMRC in the UK?

Corporation Tax is one of those responsibilities that quietly shapes your business behind the scenes. Get the timing right and everything runs smoothly. Get it wrong and you start paying extra for no real reason.

According to HM Revenue and Customs, many UK businesses end up paying interest each year due to missed deadlines or incorrect calculations. Not because they lack funds, but because the timing was off.

Here’s what you actually need to know, based on verified rules and official processes.

Corporation Tax Deadline: The Exact Timeline

Every UK limited company must pay corporation tax to HMRC based on its accounting period.

Official Rule:

• Payment deadline: 9 months and 1 day after your accounting period ends
• Filing deadline (CT600): 12 months after your accounting period ends

Example:

• Year-end: 31 March 2025
• Payment due: 1 January 2026
• Return filing due: 31 March 2026

Official guidance: https://www.gov.uk/pay-corporation-tax

One key detail many business owners overlook:

Payment always comes before filing.

Corporation Tax Rates in the UK

From April 2023, the UK introduced a tiered Corporation Tax system:

Profit Level	Tax Rate
Up to £50,000	19%
£50,000 to £250,000	Marginal Relief
Above £250,000	25%

Official reference: https://www.gov.uk/corporation-tax-rates

So when asking how much corporation tax UK businesses pay, the answer depends on your profit band.

Example:

• Profit: £40,000 → Tax: £7,600
• Profit: £300,000 → Tax: £75,000

To calculate corporation tax UK correctly:

• Start with accounting profit
• Add back disallowed expenses
• Deduct allowable expenses and reliefs
• Apply the correct rate

Accuracy here matters. Even small mistakes can lead to penalties or unnecessary payments.

Large Companies: Quarterly Payment Rules

If your taxable profits exceed £1.5 million, HMRC requires you to make quarterly instalment payments.

Payment Schedule:

• Month 7 of your accounting period
• Month 10
• Month 13
• Month 16

Official guidance: https://www.gov.uk/pay-corporation-tax-if-youre-a-large-company

This often catches growing businesses off guard, especially during rapid expansion.

Also Read – Is It Better to Take a Personal Loan or Business Loan in the UK?

How to Pay Corporation Tax HMRC Online

HMRC has made the process fully digital. You can complete your corporation tax online payment quickly and securely.

Payment Methods:

• Faster Payments (same or next day)
• CHAPS (same day, bank charges may apply)
• Bacs (up to 3 working days)
• Direct Debit
• Debit or corporate credit card

Make your payment here: https://www.gov.uk/pay-corporation-tax

Important:

Always use your 17-character Corporation Tax reference number so HMRC can correctly allocate your payment.

This is the official process for a pay online corporation tax payment.

Filing Your Corporation Tax Return (CT600)

Paying your tax is only part of your obligation. You must also submit a return.

To file and pay corporation tax to HMRC online, you need to:

• Submit a CT600 form
• Include full statutory accounts
• Provide tax calculations

Penalties:

Late filing starts at £100 and increases with continued delays.

What Happens If You Pay Late?

HMRC charges interest on late payments, calculated daily.

Interest rates are linked to the Bank of England base rate plus a margin.

While there is no fixed penalty for a one-off late payment, interest costs can add up quickly. Repeated delays may lead to further action.

Corporation Tax Time to Pay: A Practical Option

HMRC offers a Time to Pay arrangement if your business cannot meet the deadline.

You may qualify if:

• You are unable to pay on time
• Your business is financially viable
• You contact HMRC early

Learn more: https://www.gov.uk/difficulties-paying-hmrc

Key Points:

• Approval is not guaranteed
• Interest will still apply
• Early communication improves your chances

If cash flow is tight, some businesses explore structured options such as a secured business loan to improve liquidity rather than missing tax deadlines.

Do HMRC Send Payment Reminders?

HMRC may send reminders, but this is not guaranteed.

You remain responsible for:

• Tracking your deadlines
• Paying on time
• Filing correctly

Most businesses rely on:

• Accounting software alerts
• Accountant reminders
• Internal financial tracking systems

When Do HMRC Pay Tax Refunds?

If you overpay Corporation Tax or claim reliefs, HMRC may issue a refund.

Timeline:

• Usually processed within a few weeks
• Delays may occur if additional checks are required

Track your account here: https://www.gov.uk/log-in-register-hmrc-online-services

There is no fixed timeline, so avoid depending on refunds for urgent expenses.

Also Read – Best Small Business Loan Lenders for Startups and SMEs in the UK

A Practical Strategy That Works

Many experienced business owners avoid last-minute pressure by:

• Setting aside 19% to 25% of profits monthly
• Keeping tax funds separate from operating cash
• Reviewing liabilities quarterly

This reduces the need for last-minute funding such as bridging loan quick solutions and keeps financial stress under control.

Final Thoughts

Corporation Tax is predictable. The rules are clear, deadlines are fixed, and the process is digital.

Problems usually arise from poor timing, not complexity.

If you know your accounting period end date, you already know when to pay HMRC tax. From there, it becomes a matter of planning and discipline.

If cash flow is tight, act early. Delays increase costs, while early action keeps your business in control.

FAQs

• How can I file and pay corporation tax to HMRC online?

Ans. Submit your CT600 return using HMRC’s online service or approved software, then pay electronically via bank transfer, Direct Debit, or card.

• How do I pay HMRC tax online?

Ans. Log into your HMRC account, select the relevant tax, and complete payment using Faster Payments, Bacs, or Direct Debit.

• Which services offer reminders for HMRC income tax payments?

Ans. HMRC may send reminders, but most businesses rely on accounting software, accountants, or internal tracking systems.

• How do I pay my personal income tax online?

Ans. Use your HMRC online account to view your tax due and pay using approved digital payment methods.

• How can I pay my corporation tax online through official government services?

Ans. Visit the official HMRC Corporation Tax payment page, enter your reference number, and complete payment using Faster Payments, CHAPS, or Direct Debit.