Self-Assessment, why do I have to make a return and when do I have to pay?

Paula • 25 July 2024

Self-assessment is the system used by HM Revenue and Customs (HMRC) to collect Income Tax from individuals. Tax is usually deducted automatically from wages, pensions, and savings, but people who run businesses, rent property or have multiple income streams must report it in a self-assessment tax return.

Who Needs to File a Self-Assessment Tax Return?

You must send a tax return if, in the last tax year (6th April to 5th April), you were:

Self-employed as a ‘sole trader’ and earned more than £1,000 (before deducting anything you can claim tax relief on).
A partner in a business partnership.
Receiving income from renting out property.
Earning tips and commission.
Receiving income from savings, investments, and dividends.
Having a total income over £100,000.
Claiming Child Benefit and your income (or your partner’s) was over £50,000.
Make a profit (capital gain) on the sale of any assets, such as a house you don’t live in.

Key Deadlines

Registering for Self-Assessment: by 5th October following the end of the tax year you need to file for.
Paper Tax Returns: by the 31st October.
Online Tax Returns: by 31st January following the end of the tax year.
Paying Tax Owed: by 31st January following the end of the tax year.
Payments on Accounts: by the 31st July the year following the end of the tax year.

If you’ve never filed a tax return before, you will need to register for Self-Assessment online. This involves setting up an account with HMRC. After registering you will receive your 10 digit Unique Taxpayer Reference (UTR).

Completing and submitting the tax return can be a complex task. You will need details of business income and expenses, other income, pensions and dividends and other tax-deductible items such as allowances and donations. Using a professional will ensure that everything is reported correctly and that you declare and pay the correct amount of tax. Accounting professionals will have use of bespoke software through which they can file directly to HMRC saving you valuable time while also giving you peace of mind.

Tax due needs to be paid by the 31st January the following and if a payment on account is due this will need to be paid by the 31st July.

So what are Payments on Account?

Payments on Account are advance payments towards your tax bill. They are made twice a year by taxpayers who file a self-assessment tax return, with the goal of spreading the cost of the tax liability more evenly across the year.

Who Needs to Make Payments on Account?

You must make Payments on Account if your last self-assessment tax bill was more than £1,000. You do not have to make Payments on Account if more than 80% of your tax was collected at source (e.g., through PAYE).

How Payments on Account Are Calculated?

Each payment is half of your previous year's actual tax bill. For example, if your tax bill for the 2022-23 tax year was £4,000, you will make two Payments on Account of £2,000 each for the 2023-24 tax year.

When are Payments Due?

The first payment is due by 31st January during the tax year which it applies to. It is paid at the same time as the tax that is due from the previous year. The second payment is due by 31st July following the end of the tax year on the 5th April.

The Balancing Payment

If your actual tax bill for the current year is higher than the Payments on Account made, you will need to pay the additional amount by 31st January following the end of the tax year. If your actual tax bill is lower, you will receive a refund or you can offset it against future tax bills.

Adjusting Payments on Account

If you expect your income to decrease and believe your tax bill will be lower than the previous year, you can request to reduce your Payments on Account. However, if you do reduce the payment and the amount due is more than you paid you will be liable for interest payments on the unpaid amount. It is always best to complete and file the return before the end of July to be certain of the amount that is due.

Tips for Managing Self-Assessment

Keep Accurate Records: Maintain detailed records of all your income and expenses.
Use Software: Consider using accounting software to help manage your finances and make filing easier.
Plan for Payments: Set aside money throughout the year to cover your tax bill to avoid a financial crunch. And remember that if you need to make payments on account you will need to save more than just the current tax bill.
Seek Professional Help: By engaging the services of an accounting professional you will have the assurance that your tax return has been completed correctly and all relevant information has been used. Even with simple returns it is easy to make errors which could lead to costly penalties and fines… and even worse, paying more tax than you should.

M:Power Accounting are specialists in self-assessment tax and can lift the burden of compliance from you. We will ensure that your tax return is correct and filed on time. The earlier a return is filed the more accurate any reduction of payments on account will be. We don’t want you to pay a penny more to the tax man than you should.

Please contact us to see how much we can help you. Let us deal with your tax return so that you can spend more time enjoying the things you like to do.

Image credit: Photo by Nataliya Vaitkevich

S is for Specific

by Paula Veysey-Smith • 3 May 2026

Your New Year’s resolutions haven’t failed, they just need a sharper edge. Here's how one simple shift can change everything. “We make New Year's resolutions — let's call them goals. But they can be a bit vague. The way to make them happen is to actually define them better.” It's that time of year when those bold January intentions have quietly faded into the background. "Get fit." "Lose weight." "Grow my business." Sound familiar? You're not alone — and more importantly, you haven't failed. Your resolutions just need a better framework.

MTD for Income Tax Is Here: What It Means for You

by Paula Veysey-Smith • 13 April 2026

HMRC’s new system Making Tax Digital for Income Tax Self-Assessment has now arrived! This isn’t just a regulatory update. It’s a shift in how your records are kept, how often you report, and what you will need to do throughout the year. What’s changing for you: Under MTD for Income Tax, if you’re a sole trader or landlord within scope: You’ll need to keep digital records Quarterly updates will need to be digitally submitted to HMRC An End of Period Statement (EOPS) will need to filed A Final Declaration will be needed to finalise your tax position for the year In short: instead of one annual deadline, your tax reporting becomes a year-round process. Why using compliant bookkeeping software is now essential? To meet MTD requirements, HMRC requires fully digital record keeping and submissions . Manual spreadsheets alone are no longer sufficient You’ll need to use MTD-compliant bookkeeping software Sending your accountant paper records or incomplete information will cause delays The upside (it’s not just compliance) While MTD is mandatory, it also brings real benefits: Clear visibility of your tax position throughout the year Better cash flow planning Fewer surprises at year-end What support do you need to navigate this new system? The support of qualified accounting professionals is now more necessary than ever. We don’t expect you to navigate this alone and here’s how MPower Accounting can ensure that you not only comply with, but thrive under, this new reporting requirement. We’ll help you choose and set up the right software We work with trusted platforms such as Xero, QuickBooks, FreeAgent and others. We’ll recommend what fits your business best and get everything set up correctly. We’ll ensure you stay compliant Review your records regularly Submit your quarterly updates accurately and on time Handle all year-end submissions We’ll take the stress off your shoulders With the right system in place: Your records stay up to date automatically We can spot issues early You avoid last-minute pressure and surprises All we’ll need from you to make MTD work smoothly, is access to your chosen bookkeeping software, regular uploaded receipts so we can keep records current and a little of your time when there are questions. The more up-to-date your records are, the more value and proactive advice, we can provide. Your role is simple but important. Letting us take the strain of compliance will save you time and cause significantly less stress, enabling you to focus on what is important, that is running your business successfully. Next steps If you haven’t already: Speak to us about getting set up on MTD-compliant software Let us review your current bookkeeping process Make sure you’re ready for quarterly reporting

Why Cheap, Outsourced Bookkeeping Could Cost Your Business More

by Paula Veysey-Smith • 24 March 2026

When choosing an accountant, it’s natural to be drawn to lower fees. However, if your accountant outsources bookkeeping, especially overseas, it can lead to hidden risks, poorer service and long-term costs for your business. Here’s what you need to consider: Service Quality May Be Lower Higher risk of errors, misclassified transactions, and inaccurate reports Bookkeeping completed less regularly, usually only at key deadlines, eg, VAT quarter No dedicated bookkeeper which can be contacted Less Ongoing Support Little to no ongoing support from UK based accountant Less control and oversight from your accountant Slow response to queries and issues taking longer to resolve Cheap Fees Can Lead to Higher Costs You may pay more later to fix errors or redo work Risk of fines or penalties due to late or incorrect filings Your time being wasted with identifying errors and chasing a response Impact on Your Business Inaccurate financial data makes it harder to make confident decisions Delays can affect cash flow planning and reporting deadlines Frustration and lack of trust in your financial information and accountant What to Look For Instead Accountants who have UK based in house bookkeepers Clear communication and quick response times Consistent, reliable handling of your financial records Continued support and advice through the whole year Key Takeaway The cheapest option isn’t always the best value Investing in quality bookkeeping saves time, reduces risk, and gives you peace of mind The MPower team is proudly based in the UK, with every member carefully selected for their expertise and experience. Our role goes beyond simply completing bookkeeping tasks—we provide valuable insights and practical suggestions based on your financial data. We believe in building strong, partner-like relationships with our clients. That means we’re here for you all year round, whether you have a quick query or need deeper insight from your numbers to support better business decisions. We have welcomed many new clients to our portfolio who, initially enticed by the cheaper rate, have become disillusioned and disappointed with their existing out-sourcing accountants. Understanding that cheap is not the best option, they have thrived with the support and availability our team provide. Choosing the right accountant is about more than price, it’s about ensuring your business has accurate, timely financial information you can depend on and the support of an accountant who is readily available, at any time of the year. This is the service that MPower strives to provide, to any and every client!

Woman in blue sweater smiles while working on laptop at desk with headphones.

New Year Resolutions for a Stronger and more Successful Business

by Paula Veysey-Smith • 5 January 2026

As accountants, January is when we see optimism at its highest and inboxes at their fullest. A new year brings fresh energy, new goals, and the promise that this will be the year that your business really moves forward. But as the month moves on and realities hit, the elation and determination to press on with these new goals starts to fade and often die completely. The difference between a resolution that sticks and one that doesn’t is simple: clarity , practicality , and consistency . So instead of vague promises like “earn more” or “work less,” here are some realistic New Year’s resolutions that can genuinely help you build a stronger, more sustainable business. 1. Get Clear on Your Numbers (Not Just Your Turnover) One of the most powerful resolutions you can make is to truly understand your financial position. Turnover alone doesn’t tell the full story. Profit, cash flow, and margins matter far more. Ask yourself: Which services or products are most profitable? Where is cash getting stuck? What costs could be reduced without harming quality? Commit to reviewing your numbers monthly, not just at year-end. Confidence grows when decisions are backed by facts, not guesswork. 2. Improve Cash Flow, Not Just Sales Many businesses fail while still “making money” on paper. Cash flow is the lifeblood of your business. This year, resolve to: Invoice promptly and clearly Review payment terms Chase overdue payments consistently (and professionally) Small changes here can dramatically reduce stress and give you more freedom to plan ahead. 3. Price for Value, Not Fear A common issue I see is business owners under pricing, and resisting rate increases, because they fear losing customers. The result? Long hours, high pressure, and limited reward. A strong New Year resolution is to: Review your pricing Understand your true costs Charge in line with the value you deliver The right clients respect fair pricing. Better pricing attracts better clients. 4. Build Systems That Save Time If everything depends on you or a small team, your business will always feel heavy. Systems create breathing space. Resolve to: Document key processes Automate where possible Use software to reduce manual tasks Time saved can be reinvested in growth, strategy, or simply enjoying life outside the business. 5. Invest in Support (You Don’t Have to Do It Alone) Whether it’s professional advice, bookkeeping support, or mentoring, the most successful business owners know when to ask for help. This year, consider: Delegating tasks that drain your energy Seeking advice before problems escalate Surrounding yourself with people who both support, and challenge, you Support isn’t a cost—it’s an investment. 6. Protect Your Energy and Wellbeing Burnout helps no one. A business that relies on exhaustion is not sustainable. Make a resolution to: Set realistic boundaries Take proper breaks Define what “success” looks like for you, not just your business A healthy business owner makes better decisions and builds stronger businesses. Final Thought New Year’s resolutions don’t need to be dramatic to be effective. Small, intentional changes, applied consistently, create the biggest impact over time. This year, focus less on perfection and more on progress. Build a business that supports your life, not one that consumes it. If you’d like help turning your resolutions into practical actions, contact us NOW —it’s one of the smartest business decisions you can make. At MPOWER we work with business owners to provide clear direction from the numbers and strategies for success. Here’s to a calmer, clearer, and more confident year ahead.