Deciphering the Accounting Codes


From NI to UTR, VAT to PAYE there are a plethora of acronyms and codes that you are likely to come across when dealing with your business and personal finances, but do you know what they all mean or why you might need them?

Here we take a look at some of those you might come across most often and why they are important to your business.

National Insurance number (NI number)

Your National Insurance number is your own personal account number. It is unique to you and you keep the same one all your life. It makes sure that the National Insurance contributions and tax you pay are properly recorded against your name.

A National Insurance number is made up of 2 letters, 6 numbers and a final letter, for example AB 12 34 56 C.

If you are an employer then while all employees should have a National Insurance number, and provide the details to you, it is not a legal requirement to obtain work without one. However, with the introduction of Auto Enrolment Pensions (also known as AE or Workplace Pensions) it has never been more vital to obtain a National Insurance number from employees as early as possible.

Personal Unique Tax Reference number (UTR Number)

HMRC will issue you with a UTR number when you register for a Self-Assessment tax return. If you’ve already registered, you can find you UTR on various documents from HMRC.

Once you get your UTR number it stays with you all your life - in the same way as your National Insurance number but you only need a UTR number if you submit a self-assessment tax return.

It is important, as without a valid UTR number, your self-assessment tax return won’t be submitted correctly and this could result in a fine.

Company UTR Number

If you’ve set up a limited company, you’ll need a UTR number for the business. This is so that HMRC can identify which companies owe what in terms of tax.

Like a personal UTR, a company UTR is 10 digits long and will be issued to you when you register your limited company. You’ll need your company UTR number when it comes to submitting your tax return to HMRC, but don’t confuse the company UTR with other numbers that relate to your business such as company registration number of VAT number – read on to understand what these are!

Company Registration Number (CRN)

This is a unique combination of numbers and sometimes letters and is used to identify your company and verify the fact that it is an entity registered with Companies House.

Sometimes abbreviated to CRN it usually contains eight digits (e.g. 12345678) or two letters followed by six numbers. However, if you are a sole trader then you would not have a company registration number.

You’ll need to provide your CRN for a variety of reasons, but it includes when you contact HMRC, for filing tax and VAT returns and when paying your employees.

VAT Number

A VAT number is a unique identification number that’s assigned to every business registered for VAT.

UK law states that if your business’s VAT taxable turnover goes beyond £85,000, or will in the near future, then you’ll need to register for a VAT number.

If you’re already registered, you need to report your VAT at regular intervals throughout the tax year, either manually via HMRC’s website or using authorised Making Tax Digital software.

You can check the VAT number of a UK business is through the UK Government website.

PAYE Reference Number

An employer PAYE reference number, also known as an ERN, is given to every business that registers with HMRC as an employer. It is a unique set of letters and numbers used by HMRC to identify your firm.

You'll need to keep a note of this number as it’s required when you complete your end-of-year PAYE Returns and your employees might also ask for it when applying for tax credits or student loans. You may also be required to include it on payslips too so it’s an important number to have to hand!

EORI Number - Economic Operators Registration and Identification number

From January 1 2021, businesses based in Great Britain will need an EORI number(starting with GB) to import and export goods to the EU. Any business importing and exporting goods to the EU needs one, though if you only do digital services then you don’t.  You also won’t need one if you’re passing goods between Northern Ireland and the Republic of Ireland.

Visit the EORI information page on the UK government website for more information.

Personal Government Gateway user ID

The Government Gateway was a central place where you could register to use online government services. You would have used the User ID and password you received as part of the sign-up process to access lots of services, including many of HMRC’s digital services.

However, the Government Gateway was closed and substituted with replacement services in March 2019 but your Gateway ID is still active and can be used to access a variety of government services.

If you don’t already have a Gateway user ID, you won’t need to register for one. Instead, register for a unique user ID on the government service you’d like to access.

If there are any terms not covered here which you’d like clarifying, please contact our team on +44 1322555442 or email

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