Where Can I Find My TIN Number If I Live In The UK?

This blog post aims to answer the question of where can one find their TIN Number if they live in the UK. To answer this question in detail, we will explore how to find your TIN Number whether you are employed or self-employed. In addition to this, we will also discuss, how to apply for a lost TIN Number.

Where Can I Find My TIN Number If I Live In The UK?

Your TIN Number is referred to as the National Insurance Number in the UK and can easily be found in the following documents:

  • payslip 
  • P60 form 
  • letters about tax, pensions and benefits 
  • personal tax account
  • a confirmation letter from the HMRC

Your TIN Number or NINO is a combination of letters and numbers. It starts with two letters followed by six numbers and ends with either A, B, C or D. It links your national insurance contributions, tax payments, student loans as well as social security benefits.

However, when it comes to filing tax returns, individuals (and businesses) who are due for tax payments in the UK will need to use their Unique Taxpayer Reference (UTR) number. 

This is a ten-digit that is found on the front page of form SA100 or CT600 (used to file tax returns). Additionally, it can also be found on a form SA316 or CT603 (also termed as a Notice to complete Tax Return) or a Statement of Account. 

It is the combination of your NINO and UTR that replaces TIN numbers in the UK.

On the other hand, if you operate a company in the UK that trades across borders, you will need to use your UTR along with the Company Registration Number (CRN) for trading. Both these numbers will serve the purpose of TIN numbers for companies. 

The CRN is a unique combination of 8 characters, consisting of either 8 numbers or 2 letters followed by 6 numbers. It is can be found on the Certificate of Incorporation of your company.

How Can I Find My TIN Number If I Am Self-Employed?

If you are self-employed, you will need to use your Unique Taxpayer’s Reference (UTR) number as your TIN Number. 

As soon as you register yourself as self-employed or start a limited company, you will be sent your UTR number by the HMRC. it can also be called a “tax reference” number.

This is a 10-digit number found in documents such as the following:

  • previous tax returns
  • notices to file a tax return
  • payment reminders

If you are registered for self-assessment, you can also find your UTR number in your Personal Tax Account.

What Should I Do If I Cannot Find My TIN Number?

You should refer to your local tax authority if you cannot find your TIN number. If you live in the UK and have lost your TIN or National Insurance Number, you will have the following options:

  • Use an online form 
  • Calling the HMRC at 0300 200 3500 if you are in the UK
  • Call the HMRC on +44 191 203 7010 if you are outside the UK 

In either case, you should call between 8 am to 6 pm (UK time) between Monday and Friday.

The HMRC will post the details of your TIN or National Insurance Number to your registered address in their records.

If you are a self-employed individual or have set up a limited company and cannot find your Unique Taxpayer’s Reference number in any official documents, you can call the Self Assessment helpline.

In the case of a limited company, the registered owner will need to request a copy of their Corporation Tax from the HMRC. 


The above article has indicated how a taxpayer in the UK can find their TIN Number. Since TIN Numbers in the UK are a combination of one’s National Insurance Number and Unique Taxpayer’s Reference Number, different documents need to be consulted for each one. If you lose either of these numbers, you can contact the HMRC and attain the required details as long as you can prove your identity to them.


Jurisdiction’s name: United Kingdom Information on Tax Identification Numbers Section I – TIN Description The United Kingdom

Do UK companies have a TIN number?

Find a lost UTR number – GOV.UK