How To Declare Extra Income To HMRC

In today’s gig economy, many individuals are earning extra income through various means, such as freelance work, renting out properties, or running small businesses. While this extra income brings financial benefits, it’s important to understand your responsibilities when it comes to declaring it to HM Revenue & Customs (HMRC). In this blog post, we will demystify the process of declaring extra income to HMRC and provide guidance to ensure compliance with tax regulations.

Determine what Constitutes Extra Income

The first step in declaring extra income to HMRC is to determine what constitutes extra income in your specific situation. Extra income can include freelance earnings, rental income, income from selling goods or services online, tips, or any other income that is not from your main employment. Take the time to assess all sources of income outside of your regular job and identify whether they need to be declared.

Register for Self Assessment

If you have extra income to declare, you will likely need to register for Self Assessment with HMRC. Self Assessment is a system that allows you to declare and pay tax on your extra income. Registering for Self Assessment can be done online through the HMRC website, and you will receive a Unique Taxpayer Reference (UTR) number, which you will need for future tax filings.

Keep Accurate Records

It is crucial to keep accurate and organized records of your extra income and expenses. This documentation will help you complete your Self Assessment tax return correctly and accurately. Keep track of invoices, receipts, bank statements, and any other relevant documents that pertain to your extra income. Maintaining up-to-date records will make the process of declaring your income to HMRC much smoother.

Know the Deadlines

Being aware of the important deadlines for declaring extra income is essential to avoid penalties or fines. The deadline for submitting your Self Assessment tax return online is January 31st following the end of the tax year (April 5th). Ensure that you submit your return on time to avoid any unnecessary penalties. Additionally, keep in mind that payments for any tax owed are due by January 31st as well.

Complete the Self Assessment Tax Return

When it comes to declaring extra income to HMRC, the Self Assessment tax return is your key document. This form allows you to report your extra income, claim allowable expenses, and calculate the tax owed on your earnings. Completing the Self Assessment tax return can be done online via the HMRC website, or you can opt to file a paper return. Make sure to provide accurate and detailed information to avoid any discrepancies or issues.

Understand Allowable Expenses

One advantage of declaring extra income is the ability to claim allowable expenses. Allowable expenses are expenses that are directly related to the generation of your extra income, and they can be deducted from your total income, resulting in a lower taxable amount. Research and familiarize yourself with what expenses are considered allowable for your specific situation and ensure that you keep appropriate records to support these claims.

Seek Professional Advice if Needed

Navigating the process of declaring extra income to HMRC can be complex, especially if you have multiple sources of income or specific circumstances to consider. If you are unsure about any aspect of the process or have unique circumstances, consider seeking professional advice from a qualified accountant or tax advisor. They can provide guidance tailored to your situation and ensure that you comply with all tax obligations.

Pay the Tax Owed

Once you have completed your Self Assessment tax return and calculated the tax owed on your extra income, ensure that you make the necessary payment to HMRC. Failure to pay the tax owed by the deadline may result in penalties and interest charges. Utilize the various payment methods available, such as direct debit, credit card, or bank transfer, and mark the payment date in your calendar to avoid any oversight.

Keep Up with Changes in Regulations

Tax regulations and requirements can change over time, so it is important to stay informed and keep up with any updates or changes that may affect your extra income declaration. Regularly visit the HMRC website, subscribe to newsletters, or consult with a tax professional to stay abreast of any changes and ensure your compliance with current regulations.


Declaring extra income to HMRC may seem daunting at first, but with the right knowledge and proactive steps, it can be a straightforward process. Determine what constitutes extra income, register for Self Assessment, keep accurate records, meet deadlines, complete the Self Assessment tax return correctly, understand allowable expenses, consider professional advice if needed, pay the tax owed, and stay informed about changes in regulations. By following these guidelines, you can fulfill your responsibilities, maintain compliance, and ensure a smooth and transparent declaration of your extra income to HMRC. Take charge of your tax obligations, and enjoy the financial benefits of your hard-earned extra income.

Leave a Reply