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The average rating for Bark Accountants is 4.89, based on 121,181 reviews
5/5
based on 121,181 reviews
Last updated: 23 September 2025
If you’re self-employed, you probably shudder at the phrase ‘tax return’. It often feels like you’ve only just filed the last one when the time comes to prepare for the next. While the deadline for the 2024/25 tax year is approaching, understanding the process now will set you up for success. This guide explains everything you need to know.
Self-Assessment is the system HM Revenue and Customs (HMRC) uses to collect Income Tax from individuals and businesses. If you're an employee, your tax is usually handled by your employer through the Pay As You Earn (PAYE) system.
However, if you are self-employed or have other forms of untaxed income, you must declare your earnings by filing a Self-Assessment tax return each year. This is used to calculate the Income Tax and National Insurance you owe.
You generally won’t need to file a tax return if all your income is from your wages or a pension. However, you will most likely need to file one if any of the following applied to you during the tax year (6 April to 5 April):
You were self-employed as a ‘sole trader’ and your turnover (total earnings before expenses) was more than £1,000.
You were a partner in a business partnership.
You were a company director.
You earned money as a landlord by renting out property.
Your total taxable income was over £150,000.
You had to pay the High Income Child Benefit Charge because your (or your partner's) income was over £60,000.
You received £10,000 or more from savings, investments, and dividends.
You had income from abroad that you needed to pay tax on.
If you are ever unsure whether you need to file a tax return, it is always best to check with HMRC directly or consult a qualified accountant.
It’s crucial to know which deadlines apply to you. The tax year runs from 6 April to 5 April.
The filing window for this tax year opened on 6 April 2025. The key deadlines are:
Paper tax returns: Midnight, 31 October 2025
Online tax returns: Midnight, 31 January 2026
Pay the tax you owe: Midnight, 31 January 2026
Register for Self-Assessment: 5 October 2026
Paper tax returns: Midnight, 31 October 2026
Online tax returns: Midnight, 31 January 2027
Pay the tax you owe: Midnight, 31 January 2027
While the deadlines may seem far away, they can creep up quickly. It is always better to get ahead with your taxes rather than leaving things until the last minute.
Forgetting to submit your tax return or pay your bill on time will result in penalties.
Late filing: You’ll receive an immediate £100 penalty if your return is even one day late. This penalty increases significantly if your return is over three months late, with daily charges applied.
Late payment: You will be charged interest on any unpaid tax. Furthermore, if your payment is 30 days late, you'll be charged 5% of the tax owed, with additional 5% penalties at the 6 and 12-month marks.
Submitting and paying on time is the only way to avoid these escalating fees.
There are two ways to file your return: online or by post. Online is the most common method and has a later deadline.
If it's your first time filing online, you must register with HMRC first. This can take a few weeks as codes are sent by post, so do this well in advance. Once registered with a Government Gateway account, you can use HMRC's free online service.
To complete your return, you’ll need documents such as:
Your 10-digit Unique Taxpayer Reference (UTR)
Your National Insurance number
Records of your self-employment income and expenses
A P60 or P45 if you were also employed
Details of rental income, savings interest, or dividends
You can pay your tax bill via bank transfer, debit card, or cheque. Note that you can no longer pay with a personal credit card.
You don’t have to hire an accountant. However, for many people the thought of completing a tax return is overwhelming so hiring an accountant can help relieve this stress. There are several benefits to hiring a tax accountant which include ensuring your return is accurate and filed on time and claiming all allowable expenses. Seeking professional help can provide peace of mind and save you both time and money.
While the exact services included will differ depending on which accountant you hire, there are some typical services that are likely to be covered within a self-assessment service package. In short, a basic self-assessment package will cover core compliance needs, with additional services available for more complex financial situations.
Record Review: A thorough review of your income and expense documentation.
Tax Return Preparation: Completion of your SA100 tax return and any supplementary pages.
HMRC Submission: Filing the completed return directly with HMRC on your behalf.
Filing Summary: A clear explanation of the submission, your tax liability, and payment deadlines.
For clients with more intricate financial affairs, firms may offer value-added services such as:
Proactive Tax Planning: Strategic advice on legally reducing your tax liability through methods like optimising pension contributions, timing of dividend payments, or refining business structures.
Year-Round Bookkeeping: Continuous management of your financial records to ensure you are always prepared for deadlines and potential audits. If you’d like this as a standalone service, you could also hire a bookkeeper near you.
Cloud Accounting Setup: Implementation of digital platforms like Xero or FreeAgent to simplify financial tracking and ensure compliance with HMRC's Making Tax Digital (MTD) regulations.
Quarterly Financial Reviews: Regular check-ins to monitor your financial position, update forecasts, and provide ongoing strategic advice.
When engaging a service, it is always recommended to inquire whether access to financial tools or ongoing support is included in the fee, even for a one-time filing.
Like any professional service, the cost of a self-tax assessment is based on a variety of factors. In 2025, you can expect to pay anywhere from £100 to £500 but this will depend on your financial situation, business structure, and location.
The cost of hiring an accountant for your tax return depends on four main factors:
Income Complexity: A single source of income is simple and cheap to process. Costs rise for self-employment, rental income, investments, or other multiple revenue streams.
Business Structure: Sole trader returns are the most straightforward. Limited companies and partnerships are more complex, requiring additional filings and thus costing more.
Location: Fees are highest in major cities like London. Rates are often more competitive in areas like the North of England and Wales, while remote or national firms can also reduce costs.
Level of Support: A basic filing service is the most affordable. The price increases if you need comprehensive support like year-round bookkeeping, VAT returns, or strategic tax planning.
Read more in our tax preparation price guide.
The average rating for Bark Accountants is 4.89, based on 121,181 reviews
5/5
based on 121,181 reviews
Need help getting your accounts in order but unsure of costs? Read our handy price guide to find out how much hiring an accountant will cost based on the size of your business, the service you require, and much more.
