Do I Need to File a UK Tax Return This Year? A Practical Guide for Richmond Individuals

Self Assessment is not just for the self-employed. Property income, dividends, capital gains, and even life changes can trigger a filing requirement, and the penalties for missing it are real. A quick check now prevents expensive surprises later.

The most common misconception about Self Assessment is that it only applies if you are self-employed or running a business. That is understandable, it is how most people first encounter it, and HMRC’s messaging often centres on sole traders and contractors. But the reality is broader and catches many people by surprise.

If you are employed and receive a salary through PAYE, you might reasonably assume your tax affairs are settled automatically. For many people, that is true. But if you also own a rental property, receive dividends from shares, sold an asset and made a gain, earned income abroad, or experienced certain life changes during the tax year, HMRC may expect you to file a Self Assessment return, even if you have never filed one before.

The gap between “I am employed” and “I need to file a tax return” is where penalties accumulate.

Around Richmond and the wider South West London area, we see this pattern frequently. Professionals with stable employment who bought a rental property three years ago and have not thought about tax returns since. Individuals who inherited shares and now receive dividend income without realizing it creates a filing obligation. People who sold a second property or investments and assumed the gain was trivial or exempt. In each case, the person is competent, organized, and acting in good faith. They simply did not know that their circumstances had crossed a threshold that HMRC treats as requiring disclosure.

This article is a practical guide to the triggers that create a Self Assessment obligation, the deadlines that matter, and the simple checks you can do now to avoid discovering a missed filing requirement when HMRC writes to you about penalties.

What you will learn

• Why Self Assessment obligations extend far beyond self-employment, and which income sources, gains, and life events commonly trigger a filing requirement for employed individuals
• The specific scenarios we see most often in Richmond: employment plus property income, dividend income above the allowance, capital gains from property or investment sales, and overseas income or assets
• How the 60-day capital gains reporting rule for UK residential property works, when it applies, and why missing it creates a separate penalty risk
• The key deadlines for registration, paper filing, and online filing, and what happens (financially and practically) if you miss them
• A simple self-check framework to help you decide whether your circumstances require a return, and when it makes sense to get professional confirmation rather than guessing
• When straightforward situations become complex enough to need advice, and what good tax support looks like for individuals rather than businesses

Why filing triggers are often missed: the gap between “employed” and “obligated”

The UK tax system operates on the assumption that most employed people have their tax collected correctly through PAYE, and for the majority, that assumption holds. Your employer deducts income tax and National Insurance at source, reports it to HMRC, and at the end of the tax year your tax position is settled without any action required from you.

That works brilliantly when your only income is employment. It breaks down the moment you add another income source, make a capital gain, or trigger one of HMRC’s many specific reporting requirements. The problem is that these triggers are not always obvious, and HMRC does not send you a friendly reminder saying “you now need to file.” The obligation exists whether you know about it or not.

This creates a knowledge gap that is particularly common in areas like Richmond, where professionals often have layered financial lives. You might be employed full-time, own a flat you rent out, hold shares that pay dividends, have savings interest above the personal allowance, or own overseas assets. Each layer on its own might feel manageable. Together, they can create multiple filing triggers that compound if left unaddressed.

HMRC’s position is straightforward: if you have untaxed income, gains that exceed allowances, or fall into specific reporting categories, you are required to notify them and file a return. Ignorance is not a defence, and “I did not realize” does not waive penalties. That might sound harsh, but it is also predictable. The system works on disclosure, and disclosure requires you to understand when you have crossed a threshold.

The good news is that the triggers themselves are knowable. They are not arbitrary. Once you understand the common patterns, you can assess your own position with reasonable confidence, and if you are uncertain, a short conversation with an accountant will clarify it definitively.

The most common trigger: employment income plus rental property

This is the single most frequent scenario we see. Someone is employed, earning a good salary through PAYE, and decides to buy a property to let. Perhaps it is a flat they used to live in before moving, or an investment property, or a family home they have inherited and decided to rent rather than sell. The rental income starts flowing, and because it feels like “just one property” and the income seems modest after mortgage and costs, they assume it does not need formal reporting.

Whether you need to report depends on the amount and how you choose to use the property allowance.

If your gross rental income from UK property is £1,000 or less in a tax year, you can use the property allowance, which means you do not need to report the income or claim any expenses. This is the only situation where rental income does not require disclosure to HMRC. Many property investors exceed this threshold quickly and must therefore notify HMRC.

If your rental income exceeds £1,000, or if you choose to claim actual expenses (mortgage interest relief, repairs, agent fees, insurance) instead of using the property allowance, you must tell HMRC. For rental income above £1,000 and up to £2,500 (after allowable expenses), HMRC’s guidance suggests contacting them so they can adjust your tax code. For higher amounts, or if your situation is more complex, Self Assessment becomes the normal route.

In practice, most landlords exceed the £1,000 threshold fairly quickly, and most choose to claim expenses because it reduces their taxable profit. Once you are claiming expenses, you must file a Self Assessment return.

Real scenario:

“A Richmond-based solicitor bought a flat in Putney to let whilst continuing to rent herself. Rental income was £1,400 per month, mortgage and costs were £1,200, so the net felt negligible. She assumed PAYE covered everything. Three years later, HMRC wrote asking why no returns had been filed. The penalties and interest for three missed years exceeded £2,000, even though the actual tax owed was modest. The trigger was clear, she just did not know it existed.“

If your gross rental income from UK property is £1,000 or less, you can use the property allowance and avoid reporting. Above £1,000, you must notify HMRC, and depending on the amount and complexity, that usually means filing a Self Assessment return.

Dividend income: a trigger that catches shareholders and investors

If you own shares outside an ISA or pension, and those shares pay dividends, you may need to report the income to HMRC depending on how much you receive. Dividends have their own tax treatment and their own allowance, and whilst some dividend income is tax-free, anything above the threshold creates a reporting requirement.

For the 2025/26 tax year, the dividend allowance is £500. That means the first £500 of dividend income you receive is tax-free. If your total dividends for the year exceed £500, you must report the excess to HMRC. How you report depends on your existing tax position. If you already file a Self Assessment return for other reasons (rental income, self-employment, capital gains), you include the dividends there. If you are not in Self Assessment, you can often notify HMRC so they can adjust your tax code to collect the tax due, rather than requiring you to file a full return.

The complication is that many people do not track dividend income carefully. If you hold a diversified portfolio of shares, you might receive dividends from multiple companies throughout the year, each one individually small, but cumulatively exceeding £500. Or you might receive dividends from a family company, where the amounts can be substantial but feel “internal” rather than taxable. Either way, if the total crosses £500, HMRC expects notification.

Dividend vouchers or statements from your broker will show what you have received, and if you are uncertain whether you have exceeded the allowance, adding them up is straightforward. The risk is not the calculation, it is the assumption that “it is handled automatically.” It is not. Dividends outside tax-wrapped accounts require active disclosure, although the method of disclosure depends on your overall tax position.

Real scenario:

 “A higher-rate taxpayer inherited shares from a parent’s estate and continued holding them. Dividends were around £1,200 a year. Because the shares were inherited and felt like ‘family money’, he did not think of them as taxable income. HMRC identified the undeclared dividends through cross-checking with company records and issued penalties for non-filing. The tax bill itself was manageable. The surprise and the penalty process were not.“

Capital gains: property sales, investment disposals, and the 60-day rule

If you sell an asset and make a gain, you may need to report it and pay Capital Gains Tax, even if you have never filed a Self Assessment return before. The most common assets that trigger CGT for individuals are property (other than your main residence), shares and investments held outside ISAs and pensions, and certain personal possessions worth more than £6,000.

The Capital Gains Tax annual exempt amount for 2025/26 is £3,000. That means you can make gains up to this amount in a tax year without paying CGT. If your total gains exceed £3,000 after deducting allowable costs like purchase price, improvement costs, and selling fees, the excess is taxable, and you must report it through Self Assessment.

For UK residential property, there is an additional reporting requirement that operates independently of your annual Self Assessment return: the 60-day reporting rule.

If you dispose of UK residential property and a CGT liability arises, you must report the disposal and pay any tax due within 60 days of completion (this applies to completions on or after 27 October 2021). This requirement applies unless the disposal is fully covered by reliefs, for example if the entire gain is covered by Private Residence Relief. Understanding capital gains tax obligations is essential for property investors and those selling second homes.

Many people assume that because they are selling “just one property” or because the gain might be partly covered by reliefs, they do not need to report it within 60 days. That assumption is costly if a tax liability exists. HMRC’s systems track property transactions through Land Registry data, and if a disposal that creates a tax liability is not reported within 60 days, penalties start accruing automatically.

The calculation itself can be complex, especially if you lived in the property for part of the ownership period, made improvements, or are claiming reliefs like lettings relief or the final period exemption. But if there is a CGT liability, the reporting deadline is non-negotiable: 60 days from completion, regardless of whether you have worked out the exact tax due.

Real scenario:

“A couple sold a flat in Twickenham that they had bought as a first home, lived in for four years, then rented out for three years before selling. They assumed the whole gain was covered by main residence relief because they had lived there initially. It was not. The final three years created a taxable gain. They missed the 60-day deadline because they did not know it existed. By the time they filed their annual return nine months later, penalties had already been applied for the late property disposal report.“

If you dispose of UK residential property and a CGT liability arises, you must generally report it and pay the tax within 60 days of completion, unless the disposal is fully covered by reliefs such as Private Residence Relief.

 

Overseas income, gains, and assets: when geography creates filing obligations

If you are UK tax resident and you have overseas income, gains, or assets, you almost certainly need to file a Self Assessment return, even if the amounts are small. The UK taxes residents on their worldwide income and gains, subject to any relief under double taxation agreements, and HMRC requires active disclosure of foreign sources.

Common overseas triggers include rental income from property abroad, interest or dividends from foreign bank accounts or investments, gains from selling overseas assets, employment income from working abroad (even temporarily), pensions from overseas, and inheritance or gifts from non-UK sources if they produce ongoing income.

Even if tax has already been withheld at source in the foreign country, you still need to report the income in the UK and claim relief for the foreign tax paid, assuming a double taxation treaty exists. You cannot simply ignore foreign income because “it has already been taxed elsewhere.” The UK system requires you to declare it, calculate UK tax on it, and then claim credit for foreign tax, resulting in a net position.

There is also a separate reporting requirement if you hold overseas assets worth more than certain thresholds, even if they do not produce income. If your overseas assets exceed specified limits, you may need to complete additional sections of the tax return disclosing their existence and location, even if no tax is due.

Around Richmond, we see this particularly with individuals who have worked internationally, retained accounts or property abroad, or who have family connections overseas that result in cross-border financial activity. The assumption that “I am back in the UK now, so it is all sorted” is common. It is also wrong.

Life changes that trigger filing requirements: divorce, inheritance, and self-employment starts

Certain life events create filing obligations that people do not always anticipate. Divorce or separation can trigger requirements if you receive maintenance payments, transfer assets that create gains, or change your residence status. Inheritance can create obligations if you inherit income-producing assets like rental properties or share portfolios, even if you were not previously filing returns.

Starting self-employment, even on a small scale, creates an immediate registration requirement. If you begin freelancing, consulting, or running any kind of business activity, you must register with HMRC and file returns, even if your income is modest and even if you are still employed elsewhere. HMRC does not distinguish between “serious” self-employment and side projects. If you are trading, you are required to register.

Similarly, if you become a company director, even of your own limited company, you may need to file a Self Assessment return if you receive dividends or benefits that are not fully taxed through PAYE. And if you receive UK income above £100,000, you are required to file a return regardless of your other circumstances, because the personal allowance starts tapering at that threshold and HMRC requires detailed disclosure.

These triggers feel varied, but the principle is consistent: if your tax position becomes more complex than basic PAYE employment, HMRC expects you to file. The system does not send you a notification. The obligation exists the moment your circumstances change.

Deadlines that matter: registration, filing, and payment

If you determine that you need to file a Self Assessment return, the next question is when. There are three key deadlines to understand: registration, filing, and payment. Missing any of them creates financial penalties and potential interest charges.

Registration deadline: If you need to file a Self Assessment return for the first time, you must register with HMRC by 5 October following the end of the tax year. For example, if you triggered a filing requirement during the 2025/26 tax year (which runs from 6 April 2025 to 5 April 2026), you need to register by 5 October 2026. If you miss this deadline, you may still be able to register and file, but you will likely face late registration penalties.

Paper filing deadline: If you are filing a paper return, it must reach HMRC by 31 October following the end of the tax year. Most people no longer file on paper, but if you prefer this method or lack digital access, this is the absolute deadline. Missing it triggers automatic penalties.

Online filing deadline: If you are filing online (which is now the standard method), the deadline is 31 January following the end of the tax year. This is also the deadline for paying any tax due. For the 2025/26 tax year, the online filing and payment deadline is 31 January 2027. If you file late, even by one day, an automatic £100 penalty applies. Further penalties accrue if the return remains outstanding after three months, six months, and twelve months.

Payment deadline: Any tax due for the year must be paid by 31 January following the tax year end. If you owe tax and do not pay on time, interest starts accruing immediately, and additional penalties apply if the payment remains outstanding beyond 30 days. If your tax bill exceeds £1,000 and you are required to make payments on account, you will also need to pay half the following year’s estimated tax by 31 January and the other half by 31 July.

The penalties for missing deadlines are automatic and non-negotiable unless you have a reasonable excuse, which HMRC defines quite narrowly. “I did not know I had to file” is not considered a reasonable excuse. “I forgot” is not a reasonable excuse. Reasonable excuses typically involve serious illness, bereavement, or circumstances genuinely beyond your control, and you need to demonstrate that you acted promptly once the issue was resolved.

Missing the 31 January online filing deadline, even by one day, triggers an automatic £100 penalty. Further penalties accrue if you remain non-compliant. File on time, or if you cannot, contact HMRC immediately to explain why.

A simple self-check: do your circumstances require a return?

If you are uncertain whether you need to file, you can work through a short set of questions to assess your position. This is not a substitute for professional advice if your situation is complex, but it will help you identify whether you are clearly obligated, clearly exempt, or in a grey area that needs clarification.

Start with income. Do you have any income other than employment taxed through PAYE? This includes rental income above £1,000, dividends above £500, interest above your personal savings allowance, foreign income of any amount, or self-employment income. If yes to any of these, you likely need to notify HMRC, and depending on amounts and complexity, file a return.

Next, consider gains. Did you sell any assets during the tax year and make a gain? This includes property other than your main residence, shares or investments outside ISAs, or valuable personal possessions. If your total gains exceed the £3,000 annual exempt amount, you need to file. If you sold UK residential property and a CGT liability arose, you needed to report it within 60 days of completion (unless fully covered by reliefs), and you will also need to include it in your annual return.

Then check for specific triggers. Are you a company director? Did you receive income above £100,000? Do you have overseas income, gains, or assets? Did you start self-employment, even as a side activity? Did you make pension contributions that were not handled through PAYE and you want to claim higher-rate relief? Any of these create filing obligations.

Finally, consider life changes. Did you get divorced or separated and receive maintenance? Did you inherit assets that produce income? Did you move to or from the UK during the tax year? These events often create reporting requirements, even if you were not previously filing.

If you have answered yes to any of these questions, you almost certainly need to notify HMRC, and in most cases that means filing a Self Assessment return. If you have answered no to all of them and your only income is employment through PAYE, you probably do not need to file, unless HMRC has specifically asked you to. If you are uncertain, or if your answers suggest notification might be required but you are not sure of the route, that is the point at which professional confirmation makes sense.

When straightforward becomes complex: knowing when to get help

Many people can complete a straightforward Self Assessment return themselves, especially if their situation is simple: one rental property, modest dividends, or a clear capital gain with no reliefs to claim. HMRC’s online system is designed to be accessible, and if your position is uncomplicated, filing yourself can be perfectly sensible.

But certain situations move quickly from straightforward to complex, and attempting to navigate them without advice creates risk. You should consider getting professional help if you are dealing with overseas income or gains, especially if tax has been withheld abroad and you need to claim double taxation relief. If you have sold property where part of the ownership period was let, part was your main residence, and you are trying to work out how much Private Residence Relief applies.

If you have started self-employment and need to understand allowable expenses, capital allowances, or how to structure your affairs tax-efficiently.

If you are a higher or additional rate taxpayer with multiple income sources and you want to ensure you are using allowances and reliefs optimally. If you have missed previous filing deadlines and need to bring your position up to date whilst minimizing penalties. Or if you have received a letter from HMRC asking questions or raising enquiries, and you are uncertain how to respond.

Good tax support for individuals is not about creating complexity where none exists. It is about ensuring your position is reported correctly, that you are claiming everything you are entitled to, and that you understand your obligations going forward so you do not fall into the same trap next year. It should feel clarifying, not overwhelming.

A soft next step (if you are uncertain about your position)

If you have worked through this article and you are still uncertain whether your circumstances require notification to HMRC or a Self Assessment return, or if you know you need to file but you are unsure whether you can do it yourself or need support, the most useful next step is a short conversation to clarify your position. Our personal tax planning services can help ensure you are compliant and properly structured.

Xeinadin Richmond works with individuals across South West London to navigate personal tax obligations calmly and correctly. We can review your circumstances, confirm whether you need to file, help you complete returns if required, and ensure you are structured sensibly for future years. We are not here to overcomplicate things. We are here to make sure you are compliant, and that you understand why.

FAQs: the questions individuals ask about Self Assessment