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

by Paula Veysey-Smith 28 October 2025
An opportunity to sell some of your land for development can be very tempting but could you land up paying Capital Gains Tax (CGT) on your windfall. This area of tax is quite niche but knowing the rules could shape what decisions you make and it is important that you fully understand the implications. If Principal Private Residence (PPR) Relief can apply then no CGT will be due but the Revenue may well argue that is doesn’t. When does PPR apply? The relevant law is Section 222 of the Taxation of Chargeable Gains Act 1992 (TCGA 1992) . It says you don’t pay CGT on the disposal of a dwelling-house that’s been your main residence and the garden or grounds “up to the permitted area” (normally 0.5 hectares) that’s used for the reasonable enjoyment of the house. That means PPR can apply even if you sell part of your land separately — but only if it was still genuinely part of your residence at the time of disposal. However, the relief has limits: The land sold must have been enjoyed as part of the home, not used for business or rented out separately. The total area (house + garden/grounds) must not exceed 0.5 hectares (about 1.24 acres) unless a larger area is needed for the “reasonable enjoyment” of the home (which HMRC sometimes accepts for rural properties). The land must not have been sold for development before the house sale unless it clearly remains part of the residence at that time. If you sell off a piece to a developer before, or separately from, the sale of your home, HMRC can argue it’s a disposal of land and CGT would apply . HMRC’s makes its stance clear with this statement: “If the owner sells part of the garden or grounds separately from the house, relief will only apply if the land sold formed part of the garden or grounds up to the date of disposal.” How do I show that the grounds were genuinely part of the garden? If the land really is part of your garden, you can improve your position by: Showing continued use — photos, garden maintenance invoices, landscaping, etc. Avoiding any planning applications yourself before sale. Selling without fencing or subdividing it beforehand. Keeping the sale timing close to the eventual house sale (if planned). Documenting that the sale proceeds were for personal reasons , not part of a development scheme. What if planning permission is involved? If you obtain planning permission to sell at a higher value, HMRC is more likely to treat that as a capital gain so CGT will apply. If you’ve already agreed to sell the land to a developer, HMRC’s case is strong — especially if there’s planning permission or preparation for building. If you simply sold a piece of your garden that you’ve been using as part of your home, with no development activity by you , your case is stronger. However, as most developers insist on getting planning permission before the land is bought this can weaken your case. What if I’m not covered by PPR Relief? Then CGT applies on the gain you make from the sale which would be the Sales Proceeds less a portion of the original cost plus allowable expenses. Let’s look at a practical example: You bought your home + 1 acre for £400,000 total. Now you sell ¼ acre for £250,000 to a developer. You’d need to apportion the original purchase price (£100,000) to that land. Gain = £250,000 − £100,000 = £150,000. Then CGT applies at: 18% or 28% (depending on your income tax band), Less your annual CGT allowance (£3,000 for 2025/26). You can also deduct legal fees, surveyor’s fees, etc. In summary: The key factor is what the land was at the time of sale : If the sale is made before development starts, and it is still your private garden at the time of sale, PPR applies. If you had already granted rights, or if it’s no longer used as part of the garden, HMRC could argue it’s no longer part of the residence — but in your case, it’s still part of the garden when sold. Therefore, the gain should be fully exempt under PPR relief. Always seek the advice of a professional if you are considering selling land for development so that you are aware of the risks involved and the amount of CGT that may be due if PPR is not applied. Conducting the sale correctly could be the difference between a hefty tax bill or more of the funds staying in your own bank!
by Paula Veysey-Smith 16 September 2025
With the horizon of Making Tax Digital (MTD) for self-assessment very much on the landscape many small businesses are considering the benefits of incorporating a Limited Company to avoid the rigours of quarterly reporting and the new requirements of six returns being needed every year. There is much to consider when contemplating forming a limited company so let’s have a look at what this means and the benefits and disadvantages of doing so. Firstly, to understand what Making Taxing Digital means for sole traders please read our previous article at: https://www.mpoweraccounting.co.uk/how-will-i-be-affected-by-making-tax-digital-for-income-tax-mtd-for-itsa Is it easy to transfer my business to a Limited Company? You will need to firstly set up the Limited Company at Companies House. Although this can easily be done online you will need to have made decisions on the following: What’s my company going to be called? How much share capital should it have? Who are the Directors and Owners? What registered address should I use? What bank account should I set up for the new Company? How do I transfer my current business to the Limited Company? You do need to properly transfer the operations and assets to the newly formed company, you can’t just start trading through it. For this you do need professional advice to ensure it is done properly and doesn’t breach any HMRC guidelines, for example, how you value the business. Another important consideration is having to novate or assign customer, supplier and other contracts (eg, landlord) into the new business. Are Limited Companies affected by MTD? Limited Companies are not affected by MTD ITSA because they don’t file a self-Assessment return for trading profits. Instead, they file: A Corporation Tax return (CT600) once a year to HMRC. Statutory accounts once a year at Companies House. Confirmation Statement which again is filed annually at Companies House. A Personal self-assessment tax return for dividends/salary will still need to be filed if you’re a director-shareholder. This is currently outside the scope of MTD for self-assessments. If the company is VAT registered these do need to be filed quarterly under the VAT MTD which has been in place for a number of years now. What are the advantages of incorporating to avoid MTD for self-assessments? No quarterly MTD submissions unless VAT registered. Potential tax planning opportunities, e.g. mixing salary and dividends. Limited liability protection. Perception of a more credible business. What are the disadvantages of becoming a Limited Company? There are additional costs involved with running a Limited Company as the annual returns are more complicated and will require a professional to complete them properly. A Limited Company is a separate tax entity so the money in it isn’t automatically yours — you need to extract it as salary, dividend, expenses or loan. If profits are higher than £50 000 the corporation tax rate is 25% but remains at 19% below that threshold. There is marginal relief on the higher tax rate until profits are £250 000. MTD for Corporation Tax is expected eventually, so incorporation may only delay digital reporting. What are the Alternatives to incorporation? If your income will stay below the £30,000 threshold by 2027, you may never need to comply with MTD ITSA. Even if above the threshold, using cloud accounting software, e.g. Xero , QuickBooks , FreeAgent makes MTD submissions fairly painless — so incorporating purely to avoid MTD may not be the best reason. Incorporating to avoid MTD for self-assessment may seem like a good option it does come with its own complexities. If your main driver is to just avoid MTD it may not be worth it BUT if you’re already considering incorporating then now is a certainly a good time to do it. There are many positive benefits of being a Limited Company which do outweigh the additional costs especially if you are looking to grow and develop your business. Do contact us if you have any concerns about MTD for self-assessment or you’d like to discuss the merits of incorporating as we are specialists in both fields.
White Guy Fawkes mask with a smile, black eyebrows, and pink cheeks against a black background.
by Paula Veysey-Smith 26 August 2025
Have you ever been a victim of identity fraud? It’s very unpleasant, can cause financial hardship and always causes distress. My own son himself found out that he had been appointed a Director of a bogus Limited Company with no knowledge! I have also included a guide further down as to what to do if you find yourself in this unfortunately situation.
by Paula Veysey-Smith 10 August 2025
Now you can be excused if you’ve missed the announcement of the latest price increases by Xero. Apart from a rather low key “Pricing Update” notice and customer emails there has been little else published on the internet explaining the latest round of increases in the Xero Plans. So, here’s your opportunity to understand how Xero’s recent update will impact the plan you are on.
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