Most people don’t need to register for Self Assessment unless they’re self-employed, but there are exceptions. We’ll use this article to explain who does (and doesn’t) need to register for Self Assessment tax returns.

Who needs to submit a Self Assessment if they’re not self-employed?

HMRC need to know about any income you might earn to ensure you pay the right amount of tax. Not all earnings come from an employer or self-employed work though, so you might need to register for Self Assessment for other reasons too. This might be the case if you:

• Need to pay tax because you receive income from land or property which is in the UK
• Receive taxable foreign income
• Receive more than £10,000 from dividends, savings, or investments in a tax year
• Receive any taxable income which hasn’t been taxed, and it can’t be collected through your tax code
• Need to pay the High Income Child Benefit Charge (HICBC) because you receive Child Benefit and you or your partner have an individual income which is more than £60,000, and you don’t want to use the digital service to have HICBC collected through your tax code by your employer.

The requirement to submit a tax return purely because you earn more than £150,000 per year has been removed for 2024/25.
 

How do I register for Self Assessment if I’m not self-employed?

The process of registering for Self Assessment depends on whether you’re self-employed or not. If you’re not self-employed, you can either complete and submit a SA1 form by post, or register online (which tends to be a lot faster).

When should I register?

If you didn’t send a tax return last year, you’ll need to register for Self Assessment by 5th October following the end of the tax year that you need to submit a return for. Your first tax return will then be due by 31st January the following calendar year if you submit online. The deadline is 31st October the same year if you submit a paper return.

For example, if you need to submit a tax return for the 2024/25 tax year, then you must sign up for Self Assessment before 5th October 2025.

What happens after I register for Self Assessment?

HMRC will send you a Unique Taxpayer Reference (UTR). If you’re a company director, this UTR number will be different to the one you received for your limited company – so don’t mix them up!

You will also receive reminders when your tax return is due. If your situation changes and you no longer need to submit, you should let HMRC know as soon as possible.

When you first sign up for HMRC’s online services (which you’ll use to complete your Self Assessment tax return) you’ll receive an activation code. This can take a few weeks to arrive, so be sure to register in plenty of time to submit your return.

 
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