HMRC warning people have just three days to avoid £100 fine

People who have pocketed a few extra quid have just days to let the HMRC know. People who have made more than £1,000 from side gigs in the last tax year are being warned to register for self-assessment.

Missing the October 5 deadline for registration and subsequently failing to submit a timely tax return could result in a penalty.

A side-hustle refers to any activity you undertake to supplement your income, such as online selling, freelance work in addition to your regular job, or earning from tasks like pet-sitting, dog walking, or babysitting.

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The amount you rake in matters. If your hustle brings in less than £1000 in a tax year, it's not considered taxable income, and there's no need to declare it.

However, once your earnings exceed this limit, you must register as self-employed and begin paying tax on the income over this threshold. Missing out can mean a fine of £100.

This threshold is calculated based on your profit after deducting expenses. For example, if you're crafting and selling jewellery, you can subtract the cost of materials from your total earnings.

You're only required to file and pay tax if your remaining profits exceed £1,000 for the year.

Registration is also necessary if any of the following applied in the past year:

• you operated as a sole trader.

• you were a partner in a business partnership.

• your total taxable income exceeded £150,000.

• you had to pay Capital Gains Tax when you sold or 'disposed of' something that appreciated in value.

• you were liable for the High Income Child Benefit Charge.

You may also need to register and submit a tax return if you have untaxed income, such as earnings from property rental, tips and commission, or income from savings, investments and dividends.

The deadline for registration is October 5. There's no penalty for registering after this date, but if you haven't registered, filed your tax return, and settled your bill by January 31, you will incur a fine.

If you do miss the October 5 deadline, it's advised to register as soon as you can. This ensures you're set up and ready to file your return on time.

HMRC imposes interest on overdue tax payments. The interest is applied from the due date of the payment until the actual payment date and is automatically added.

There's a handy calculator on the gov.uk website that can help you work out what your late payment charges will be, should you miss the deadline.

You can contest any penalties if you have a valid reason. You typically have 30 days from when your penalty was issued to get in touch with HMRC or lodge an appeal.

If you miss this deadline, you'll need to provide a justification.