HM revenue and customs (The HMRC) issues the unique taxpayer reference to customers; so, When someone or a client of yours registers for the purpose of self assessment, it contains ten digits. Lets take an example here; when we talk about ten numbers it is like, 1324657980 and if you want to locate it, you can easily find it on your tax return. HRMC also issues some other documents it can also be found there if you want to. If you or your client is not registered for the purpose of self assessment then you should get registered as soon as possible.
When your status changes to self employed you need to tell the HRMC as quick as possible and get UTR number and you should inform HMRC. if you still don't have your UTR number then the easiest and fastest way to get that is you should go to their website, and in their websites you will find a link below which will require your information which is important for getting the UTR number. It includes your phone number, your present address, your permanent address, and ID number also. Remember to take care that you must be filling your own tax return. The HMRC sends notification to you and you must receive that notification in at least six weeks. You will be in their record and they will contact you for further information they need in future like your personal information.
There are always invoices that are made by you so it's important for you to check those invoices for further information on the UTR number. When it comes to your NI contributions and tax, you need to understand that you are responsible for your own tax issues. This means that you should take good care of it. You must keep it safely so that you don't lose it because that can create a lot of problems for you in the future.
All in all, I would advise you to make sure that you take a look at the unique tax reference and make sure that you don't disappoint yourself in any way. If you have the right UTR, you will have your taxes properly prepared because the UTR number is an integral part of any correspondence with the HMRC. Without this number, you definitely won't be able to communicate well with the HMRC, and your process of paying taxes will not be smooth at all.
www.utr.org.uk, If you would like to learn more about Unique Tax Reference