What documents do I need to provide when registering for self-employment?

To register for self-employment with HMRC, you will need to provide certain documents. Firstly, you will require your National Insurance number, as it is crucial for tax and contribution purposes. Additionally, you must furnish your personal details such as your full name, address, contact information, and date of birth. You may need to provide proof of identity, which can be in the form of a passport, driver's license, or national identity card. Moreover, you should have your business details available, including the date you started your self-employment, nature of your business, and estimated annual income. It is important to have records of any business expenses or income earned so far. Lastly, you may also need to provide your Unique Taxpayer Reference (UTR) if you have previously been registered with HMRC.