Corporation Tax Payment Reference — How to Pay HMRC Correctly

Getting your payment reference wrong is one of the most common Corporation Tax mistakes — and it can lead to HMRC chasing you for tax you've already paid. Here's exactly how to get it right.

What is a Corporation Tax payment reference?

Your Corporation Tax payment reference is a unique code you use when paying your Corporation Tax bill. It tells HMRC which company and which accounting period the payment is for.

If you use the wrong reference, HMRC can't match your payment to your return. You'll get automated reminders, then penalty notices, then interest charges — all while the money sits in HMRC's account, allocated to nobody.

Your payment reference — how to find it

Do not try to construct your payment reference from the period end date. HMRC assigns a unique reference to each accounting period. The correct reference is on:

• Your Corporation Tax payslip (sent when your return is due)
• Your HMRC Business Tax Account — log in at www.gov.uk/log-in-register-hmrc-online-services, select 'Corporation Tax', then 'View return deadlines and make a payment'

What the reference looks like

Your payment reference is 17 characters long, in the format:

[10-digit UTR]A001[PP]A

Where:

• UTR = Your 10-digit Unique Taxpayer Reference
• A001 = Fixed sequence (always these four characters)
• PP = 2-digit sequential period number assigned by HMRC (01 for your first CT accounting period, 02 for the second, and so on)
• A = The letter A (always, at the end)

Example: For a company with UTR 1234567890 on their first Corporation Tax accounting period, the reference would be 1234567890A00101A.

Always use the reference shown in your HMRC account or on your payslip. The period sequence number is assigned by HMRC and cannot be reliably worked out from the period end date — using a guessed reference means your payment may not be matched to the right return.

Where to find your UTR

Your Unique Taxpayer Reference is on:

• The letter HMRC sent when you registered for Corporation Tax
• Previous CT600 returns
• Your Government Gateway account (under 'Business tax account')
• Any correspondence from HMRC about Corporation Tax

If you've lost it, call HMRC on 0300 200 3410. They'll verify your identity and tell you your UTR.

How to pay Corporation Tax

Online banking (same day)

Transfer the payment to:

• Sort code: 08 32 10
• Account number: 12001039
• Account name: HMRC Cumbernauld
• Reference: Your payment reference (from your HMRC account or payslip)

This is the fastest method — payment is usually processed the same day.

Direct Debit

Set up via your HMRC online account. Takes 3 working days to process. You need to set this up before your payment deadline.

CHAPS (same day)

Same bank details as online banking. CHAPS payments arrive the same day but your bank may charge a fee (typically £20-30).

Bacs (3 working days)

Same bank details. Allow 3 working days for the payment to reach HMRC.

Corporate credit/debit card

Pay through HMRC's online service. Credit card payments incur a fee. Debit cards are free.

At your bank or building society

Use payslip from HMRC's payment booklet. This is the slowest method — allow 3 working days.

Payment deadline

Corporation Tax must be paid by 9 months and 1 day after the end of your accounting period.

The payment deadline is different from the filing deadline. You can file your CT600 up to 12 months after the period end — but the tax must be paid earlier.

If your profit exceeds £1.5 million, you must make quarterly instalment payments. Most small companies don't need to worry about this.

What happens if you pay with the wrong reference?

If HMRC can't match your payment:

1. Week 1-4: Payment sits in HMRC's suspense account
2. Month 1: You receive an automated reminder that your tax is unpaid
3. The day after your 9m+1d payment deadline: If the payment hasn't been matched and applied to your account by then, late payment interest begins accruing at 7.75% per year (current rate from 9 January 2026), calculated daily. If the money is already in HMRC's account, this interest will be reversed once the payment is correctly reallocated — but you need to act quickly.

To fix it, call HMRC on 0300 200 3410 with:

• Your UTR
• The amount you paid
• The date you paid
• Your bank reference / transaction ID
• The correct accounting period

HMRC will reallocate the payment. Interest charges should be reversed once they confirm the payment was made on time.

What if you can't pay on time?

Contact HMRC before the deadline. They can arrange a Time to Pay agreement — a payment plan that lets you spread the bill over several months.

Call the Payment Support Service on 0300 200 3835. Have your UTR and details of your financial situation ready.

A Time to Pay agreement:

• Prevents further enforcement action
• Doesn't stop interest accruing (you'll still pay interest)
• Typically allows 6-12 months to pay
• Must be agreed before the deadline where possible

Common payment mistakes

1. Using an incorrect or guessed payment reference

Never try to construct your reference from the period end date — it will be wrong. Log in to your HMRC Business Tax Account or check your CT payslip to get the exact 17-character reference HMRC has assigned to that period.

2. Confusing filing and payment deadlines

Filing deadline: 12 months after period end. Payment deadline: 9 months and 1 day after period end. The payment deadline comes first.

3. Paying from a personal account

Always pay from the company's bank account where possible. If you pay from a personal account, the reference is even more important — HMRC has no other way to identify the payment.

4. Rounding the payment

Pay the exact amount shown on your CT600. Don't round up or down — it can cause matching issues.

5. Missing the deadline by a day

HMRC's systems are automated. Even one day late triggers interest charges at 7.75% per year (current rate). Set a calendar reminder for 2 weeks before the deadline.

Taxpipe calculates your payment deadline

When you file your CT600 with Taxpipe, we show you:

• The exact amount of Corporation Tax owed
• Your payment deadline
• Your payment reference (from your HMRC account)
• HMRC's bank details

Everything you need to make the payment correctly, in one place.

File your CT600 for £59 →

Related Articles

• Quarterly Instalment Payments: Who Needs to Pay and When

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