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Self Assessment Tax Return made simple.

Make tax season easy with Online FIlings. Quickly file a self assessment tax return with HMRC hassle-free. Easy, efficient, with expert support - get started now!

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Filing your Self-Assessment Tax Return is as easy as 1 | 2 | 3

1. Answer a few questions regarding your income and expenses
We’ve simplified the filing process by creating a streamlined jargon- free tax questionnaire which includes useful tips for a step by step support. You’ll only be asked to answer questions relevant to your specific situation.

2. Submit and file your income tax return securely with HMRC
Online Filings self assessment filing software is recognised by HMRC meaning that it has been tested by HMRC and we hold an electronic link with them. Your return is filed instantly as soon as all necessary information is provided.

3. Get unlimited support throughout your filings from an experienced team
Our customer experience team is available promptly during office hours by chat, email and phone to smooth-out your filing experience, should you need assistance when using the software.

Our software supports a wide range of income sources

Employment types

  • Employment - SA102 Full/Short
  • Self-Employment - SA103 Full/Short
  • Property - SA105

Income types

  • Foreign Income - SA106
  • Capital Gains - SA108
  • Residency - SA109

Frequently Asked Questions

What are the reasons for me to file a tax return?

  • You are self-employed (a 'sole trader') and earned more than £1,000 in the previous tax year
  • You are a partner in a business partnership
  • You are a company director
  • You are renting out a property
  • You have taxable income from savings
  • You have investments
  • You receive dividends
  • You have a foreign income
  • You want to claim some Income Tax Relief
  • You have other non-taxed income at source
  • You have annual income of £100,000 or more before tax
  • You have capital gains or loss to claim

Why should you use an accountant to file your Self Assessment tax return?

An accountant will check your data to make sure you do not make any mistakes and you can ask them for advice regarding any queries. An accountant has experience in preparing tax returns and can help you identify tax regulations which apply to your situation.

Moreover, accountants have knowledge about the tax system and legislation which can add value to your tax planning. Furthermore, accountants can help you communicate with HMRC and help with any disputes (to help prevent legal action).

When does the personal tax year start and end?

The personal tax year starts on 6 April and ends on 5 April of the following year.

The last tax year started on 6 April 2022 and ended on 5 April 2023. This means that we are reporting income sources between those dates.

How do you pay Self Assessment tax?

We recommend paying your tax via bank transfer.

You would pay the bank account listed below:
08-32-10 - 12001039 - HMRC Cumbernauld

Your payment reference is your ten-digit UTR (Unique Tax Reference) number followed by the letter k at the end.

You can also log in to your HMRC account and pay via card.

How long do I need to keep my records for tax purposes?

You have to keep your records for at least 5 years from the January 31st submission date of the relevant tax year, as HMRC may request additional information in the future (for example, for auditing purposes).

Do you need to include ISA income on your tax return?

You do not need to declare any income on your ISA account as the income generated on those accounts are tax-free. This includes all types of ISA (cash ISAs, stocks and shares ISAs, innovative finance ISAs, Lifetime ISAs and Junior ISAs).

If you have reached 55 years of age and have taken out 25% of your personal pension pot as a lump sum, do you need to declare this?

When you reach 55, you can take up to 25% of your pension pot tax-free and it is separate from your personal allowance. Funds taken out of your pension pot up to 25% of your total pension pot do not need to be declared on your tax return.

How do you calculate capital gain or loss on simple personal assets disposal (not related to property)?

To calculate gain or loss simply deduct the disposal price from the purchase price. You can also deduct the cost associated with asset purchase and disposal.

When is the submission deadline for Self Assessment?

The deadline for paper submissions is midnight 31 October of the same year. For example, for the tax year ending on 5 April 2023 the deadline for paper submissions is 31 October 2023.

Nowadays people are filing their tax returns online. The submission deadline for online tax returns is midnight 31 January of the following year. For example, for the tax year ending on 5 April 2023 the deadline for online submissions is 31 January 2024.

What happens if you miss a deadline?

If you are late with your tax return submission you will be charged with penalty and interests:

  • If you miss the submission deadline you are charged a flat penalty of £100.
  • If you are 3 months late with the submission, a daily penalty of £10 per day for up to 90 days (maximum £900) is added to your initial penalty.
  • If you are 6 months late with the submission, you will pay an additional penalty of 5% of the tax due or £300 (whichever is greater).
  • If you are 12 months late with the submission, you will pay yet another additional penalty of 5% of the tax due or £300 (whichever is greater).

Separately, you will also be charged for late tax payments:

  • If your payment is late for more than 30 days you will be charged 5% of your tax.
  • If you are 6 months late with the payment, you will incur a penalty of 5% of the outstanding tax.
  • If you are 12 months late with the payment, you will incur an additional penalty of 5% of the outstanding tax at that time.

You are allowed to appeal against a penalty if you have a reasonable excuse.

What are the reasonable excuses to appeal against a penalty?

Reasonable excuse are excuses which prevented you from filing the tax return. Some examples of reasonable excuses are:

  • Death of a close relative
  • Hospitalisation
  • Issues with HMRC online services
  • Natural disasters (e.g. flood, fire, etc.)
  • Disability-related delays
  • Covid-19

Example excuses not accepted by HMRC:

  • Failure of a 3rd party submission
  • Failure to pay due to lack of funds
  • Not receiving HMRC reminders
  • Mistakes in tax return
  • You are allowed to appeal against a penalty if you have a reasonable excuse.

What happens if you make a mistake on your tax return?

If you made a mistake on your tax return, you can still make amendments even after submission. You have 12 months after the original submission deadline to file the amended tax return. For example, for the tax year ending 5 April 2022 you can file amendments by 31 January 2024.

What are Capital Gains Tax (CGT) exemptions?

Capital Gains Tax is a tax on the profit when you sell (or ‘dispose of’) something (an ‘asset’) that’s increased in value.

  • When you transfer your assets to your spouse or civil partner then you are not liable to Capital Gain Tax.
  • You may not be liable to Capital Gains Tax if you make a gain when selling personal items for less than £6,000.
  • You do not pay CGT on your car (unless used for business purposes).


Who needs to register for Self Assessment
Before you can file a tax return, you will need a UTR number so HMRC can create account for you.
Here are some of the people who might need to file:


You earn more than £100,000


Airbnb hosts

You earn more than £1,000 from a side gig


Crypto investors

You earn foreign income