How to Pay Self Assessment Tax Bill

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You pay your self assessment tax bill to HMRC, and the fastest route is approving the payment through your bank app with Open Banking, which settles the same day. The bill for the 2025/26 tax year is due by 31 January 2027.  Whatever method you use, quote your Unique Taxpayer Reference followed by the letter K, or HMRC cannot match the money to your record.

The 31st January deadline is the most critical date in the calendar for sole traders and freelancers. But filing your return is only half the battle you actually have to pay the bill. In recent years, HMRC has modernised its payment systems. The days of relying solely on slow postal cheques are gone. Today, the quickest and safest ways to pay Self Assessment tax are digital, often settling your bill instantly.

IBISS & CO This guide breaks down exactly how to pay HMRC Self Assessment, which methods are instant, and what to do if you cannot afford to pay on time.

Which Deadline Applies to You

Most people pay once a year, by 31 January. If your last bill was more than £1,000 and you do not pay most of your tax at source, HMRC also asks for payments on account, which are two advance instalments toward next year’s bill.

Deadline What is due for 2025/26
31 July 2026 Second payment on account
31 January 2027 Balancing payment, plus first payment on account for 2026/27

How Long Does Payment Take?

If the deadline is approaching, speed matters. Use this table to choose the proper method.

Payment Method Processing Time Best For
Approve via Bank App
(Open Banking) 		Instant / Same Day Last minute payments ★Recommended
Debit Card
(Online) 		Same Day Paying quickly online
Corporate Credit Card Same Day Businesses (Fees apply)
Direct Debit
(Set up new) 		5 Working Days Planning ahead
Direct Debit
(Existing) 		3 Working Days Regular payers
Bank Transfer
(Bacs) 		3 Working Days Manual payments
Cheque 3 Days + Post Paper trail (Slowest)

The Fastest Way to Pay (Recommended)

If you are paying close to the deadline, we strongly recommend using HMRC’s Pay by bank account service or the HMRC App. These methods use Open Banking technology which is instant, secure & reduces the risk of typing errors.

1. Pay via the HMRC App

This is currently the simplest way to manage your tax bill.

  1. Download the free HMRC App and sign in.
  2. Select Pay and choose Approve a payment through your open banking account.
  3. The app will open your mobile banking app automatically.
  4. You simply approve the amount.

Why we recommend this You do not need to type in your UTR number or HMRC bank details manually. The app pre fills this information to make sure your money goes to the right place.

2. Pay Online via Bank Transfer Open Banking

If you prefer using a desktop or laptop:

  1. Log in to your HMRC online account.
  2. Select Pay by bank account.
  3. You will be redirected to your bank’s online portal to authorise the payment.

3. Paying by phone

You cannot pay HMRC by card over the phone. To pay by phone, use your own bank’s telephone banking service to send a Faster Payment to HMRC, with the account details below and your UTR plus K as the reference. It clears the same way as an online transfer, usually the same or next day.

Paying by Debit or Credit Card

You can pay your tax bill online using a debit or corporate credit card. However there are strict rules regarding credit cards that often catch taxpayers out.

  • Debit Cards: Accepted There is no fee.
  • Corporate Credit Cards: Accepted HMRC charges a fee (added to the transaction) because they are charged by the card provider.
  • Personal Credit Cards: Not accepted. You cannot pay Self-Assessment bill with a personal credit card directly to HMRC.
pay self assessment tax

Slower Payment Methods Plan Ahead

If you have completed your return weeks in advance, these traditional methods are perfectly fine. Just be aware of the processing times.

Bank Transfer (Bacs / CHAPS)

You can make a manual transfer from your bank. You must ensure you use the correct details to avoid your payment being lost in the system.

  • Sort Code: 08-32-10
  • Account Number: 12001039
  • Reference: [Your 10 digit UTR Number] followed by the letter ‘K’.

Example: 1234567890K

 Use Cumbernauld unless HMRC has specifically told you to pay into Shipley. Always double-check the back of your payment slip or the GOV.UK website to confirm. 

Do not copy these details from a chatbot answer. If a single digit is wrong, your payment may not reach HMRC in time. Our guide on whether you can trust ChatGPT with your tax return explains where AI tools most often get UK tax wrong.

Setting up a Direct Debit

You can set up a Direct Debit to take payment automatically.

  • If you have set one up before: Allow 3 working days before the deadline.
  • If this is your first time: You must allow at least 5 working days for the mandate to be set up. Do not leave this until the 30th of January.

Posting a Cheque

While we generally advise against it due to the risk of postal delays, you can still pay by cheque.

  • Make the cheque payable to ‘HM Revenue and Customs only’.
  • Write your UTR number followed by ‘K’ on the back.
  • Include your paying-in slip (if you have one).
  • Post it to: HMRC, Direct, BX5 5BD.

Can I Pay in Instalments?

If you cannot pay your full tax bill by the 31st January deadline, do not ignore it. Ignoring the bill will result in penalties. You may be eligible to set up a Time to Pay arrangement online if:

  • You have filed your latest tax return.
  • Owe less than £30,000.
  • You are within 60 days of the payment deadline.
  • You plan to pay off your debt within the next 12 months.

If you meet these criteria, you can set this up via your Government Gateway account without speaking to anyone. If you owe more than £30,000 or need longer to pay, you must call the HMRC Payment Support Service.

Need support? Negotiating with HMRC can be daunting. If you are struggle to manage your tax liabilities, Book Meeting with IBISS & CO. Our team can review your situation & advise on the best option for action.

What are the Penalties for Late Payment?

HMRC is strict with deadlines. Even if you cannot pay, you must file your return on time to avoid the initial £100 filing penalty. If you are late paying your tax bill:

  • 30 days late: A 5% penalty is charged on the tax owing.
  • 6 months late: An additional 5% penalty is charged.
  • 12 months late: A further 5% penalty is charged.

Interest: Interest is charged daily on all unpaid tax from 1st February.

Frequently Asked Questions

How long does it take for HMRC to receive my payment?

Approval through your bank app or paying by online or telephone banking (Faster Payments) usually reaches HMRC the same day or the next working day, including weekends. An existing Direct Debit and Bacs take about three working days. A first Direct Debit takes about five.

No. HMRC stopped accepting payments at the Post Office several years ago. You must use one of the digital or banking methods listed above.

Your payment reference is your 10-digit Unique Taxpayer Reference (UTR) followed by the letter K. It is essential you include this, or HMRC cannot allocate the money to your account.

No. The BillPay service has been discontinued. Use the HMRC App or online bank transfer instead.

Need Help with Your Tax Return?

IBISS & CO. specialise in helping landlords,sole traders and businesses manage their tax compliance efficiently. Do not wait for the deadline stress to hit. Contact us today for expert assistance .