Small changes to Self Assessment can create disproportionate work for practices. For 2025/26, close-company disclosures, Winter Fuel Payments and voluntary returns deserve particular attention.
Self Assessment season is rarely just about completing the return in front of you, explained Helen Thornley in a recent webinar.
You also need to spot income thresholds, collect information HMRC may not already hold and understand where its systems can create additional work.
For 2025/26, several areas deserve an extra check before returns are submitted.
1. Think carefully before submitting a voluntary return
A voluntary return is, broadly, a Self Assessment return that HMRC is not expecting.
There can be an understandable temptation to submit one. A client may already have a Unique Taxpayer Reference (UTR), while their income remains complicated enough that a tax return feels like the simplest approach.
The problem is what happens afterwards.
As discussed in the webinar, an unexpected return can cause problems with repayments. It can also interact badly with Simple Assessment because HMRC systems do not necessarily treat the two processes as one joined-up exercise.
The practical message is straightforward: if a client needs to return to Self Assessment, make sure HMRC is expecting the return before submitting it.
HMRC's current guidance confirms that clients previously registered for Self Assessment may need to reactivate their account. Agents can also contact HMRC about Self Assessment registration or reactivation.
That extra step upfront may be preferable to resolving an unexpected repayment or assessment afterwards.
2. Collect the new information required from close-company directors
The 2025/26 return brings additional reporting for people who have been directors of close companies during the tax year.
Where the individual is already completing a Self Assessment return, the additional information can include the company's name and registration number, dividends received from the company and the individual's highest percentage shareholding during the year.
HMRC's 2025/26 employment pages also contain specific questions covering company directors and whether the company was a close company.
For practices, the important point is operational.
Some of this information may not previously have formed part of your standard personal tax information request. In particular, determining the highest percentage shareholding during the year may require additional work where shareholdings have changed.
Review your Self Assessment information requests now rather than discovering missing information when the return is ready for submission.
3. Ask clients about Winter Fuel Payments
Winter Fuel Payments introduce another potential information point for 2025/26 returns.
Where an individual's total income exceeds £35,000, HMRC applies a charge equal to the full Winter Fuel Payment received. The test applies to the individual's income rather than their partner's income, and there is no taper above the threshold.
Importantly, the relevant measure is total income rather than adjusted net income. HMRC guidance confirms that Gift Aid donations and relief-at-source pension contributions do not reduce that total-income figure for this purpose.
For online Self Assessment returns, HMRC says it will include the Winter Fuel Payment automatically where possible. However, taxpayers should check the amount and add it themselves when it is missing. Paper filers need to add the payment themselves.
That makes a client question worthwhile even when you expect pre-population to do the work.
4. Watch the thresholds where small amounts can have large consequences
The webinar also highlighted a broader lesson for client reviews: seemingly minor amounts of additional income can matter.
Examples discussed included the High Income Child Benefit Charge, the withdrawal of the personal allowance and the loss of childcare support at higher income levels.
This is where incomplete information can become expensive.
A client may assume that a small amount of savings income is irrelevant. From the adviser's perspective, however, it can affect whether an income threshold has been crossed.
The practical response is not to focus only on the client's largest income sources. Make sure your information-gathering process captures the smaller amounts as well.
Pension contributions and Gift Aid may also be relevant when reviewing adjusted net income, depending on the client's circumstances. Individual advice should, of course, reflect the rules applying to that client and tax year.
5. Build a repeatable process for overpayment relief claims
Overpayment relief was another recurring problem raised during the session.
The difficulty can run in both directions. HMRC may receive claims that do not contain all the required information, while advisers may encounter rejected claims they believe were correctly prepared.
For practices making these claims regularly, a consistent template can help.
Rather than drafting each claim from scratch, build or use a pro forma that covers the statutory requirements. Then make sure each claim contains the necessary client-specific information before it leaves the practice.
If a correctly prepared claim is repeatedly rejected, retain the evidence. The webinar's advice was to raise persistent problems through the relevant professional body so there is a concrete example to take back to HMRC.
6. Use the right escalation route when HMRC processes break down
Not every HMRC problem needs to begin with a formal complaint.
The webinar highlighted several ways advisers can report problems with GOV.UK guidance and online services. It also covered escalation routes for client-specific cases where normal channels have stalled.
The underlying principle is useful: give HMRC enough evidence to identify the specific failure.
That might mean reporting a broken page from within the service itself or documenting a case where an expected response has not arrived.
The more precisely you can identify the client, process and point of failure, the easier it becomes to investigate what went wrong.
Prepare the process, not just the return
The common thread across these issues is preparation.
Check whether HMRC expects the return. Gather close-company information earlier. Ask about Winter Fuel Payments rather than relying entirely on pre-population. Capture all relevant income before assessing threshold effects.
And where a recurring administrative problem exists, create a standard process rather than solving it from scratch each time.
Those small changes can reduce avoidable work during the busiest part of Self Assessment season.
Self Assessment 2025/26 FAQs for accountants
What has changed on Self Assessment returns for close-company directors in 2025/26?
For tax years after 2024/25, someone completing a personal tax return who was a director of a close company must provide additional information. This includes the company's name and registered number, dividends received from that company and their percentage shareholding. If their shareholding changed during the year, they must report the highest percentage held.
For accountancy practices, this may mean collecting information that was not previously part of the standard personal tax return process.
What information should accountants collect from close-company directors?
Where a client was a director of a close company during the tax year, accountants may need to establish:
- the company's name and registered number;
- how much dividend income the client received from that company; and
- the client's percentage shareholding, including the highest percentage held if it changed during the year.
These additional reporting requirements apply to personal returns for tax years after 2024/25.
Practices should consider whether their Self Assessment information requests need updating to capture these details.
Do directors have to report dividends from their own close company separately?
Yes. Where someone completing a personal tax return was a director of a close company, the additional information includes dividend income received from that company during the relevant year. The regulations specifically provide for the reported dividend amount to be zero where no dividends were received.
This is separate from simply establishing the client's overall UK dividend income when preparing their return.
What shareholding percentage must a close-company director report?
The return requires the percentage of the close company's share capital held by the individual. If that percentage changed during the tax year, the individual must report the highest percentage held during that year. The reported percentage can also be zero.
That means practices may need to establish whether shares were issued, transferred or otherwise changed during the year rather than relying solely on the year-end position.
Should you submit a Self Assessment return if HMRC is not expecting one?
Accountants should first establish whether the client needs to submit a return and whether their Self Assessment account needs reactivating.
HMRC currently advises that someone previously registered for Self Assessment who did not submit a return in the previous year may need to reactivate their account. Its online registration service identifies the appropriate process.
This can be particularly important where a client retains a Unique Taxpayer Reference but has previously left Self Assessment.
Does having a UTR mean a client should submit a Self Assessment return?
Not necessarily. A Unique Taxpayer Reference shows that the individual has been registered with HMRC, but their current filing position should still be checked.
HMRC advises people who were previously registered but did not submit a return in the preceding year to check whether they need to reactivate their Self Assessment account.
For advisers, the practical point is to establish the client's current Self Assessment status rather than treating possession of a UTR as sufficient reason to file.
How does the Winter Fuel Payment affect Self Assessment?
If an individual's total income is over £35,000 and they receive a Winter Fuel Payment, HMRC will recover an amount equal to the payment. Where the individual completes a Self Assessment return, the amount is recovered through their tax bill rather than through PAYE.
For online returns, HMRC says it will usually include the Winter Fuel Payment amount automatically. The taxpayer or adviser should still check that the information is correct.
What is the income threshold for paying back the Winter Fuel Payment?
The threshold is total income over £35,000. If total income exceeds £35,000, the charge equals the full Winter Fuel Payment received. It is not a tapered charge.
The individual's partner's income does not count towards their £35,000 total-income test.
Is the Winter Fuel Payment itself taxable income?
HMRC describes the Winter Fuel Payment itself as non-taxable. Instead, where the individual's total income exceeds £35,000, an equivalent Income Tax charge applies.
For Self Assessment clients, that distinction matters when reviewing the calculation: the mechanism is a separate charge rather than treating the payment itself as ordinary taxable income.
Will HMRC automatically include the Winter Fuel Payment on an online tax return?
Usually. HMRC's current guidance says that where someone files their Self Assessment return online, HMRC will usually include the amount automatically. It appears as the Winter Fuel Payment charge and forms part of the tax calculation.
Accountants should still check the amount rather than assuming pre-populated information is complete or correct.
Why should accountants check small amounts of additional income?
Small amounts of income can matter where a client's tax position depends on an income threshold.
The webinar highlighted the importance of obtaining complete information rather than focusing only on a client's largest income sources. Depending on the client's circumstances, additional savings or other income may affect threshold-based tax charges or allowances.
The appropriate threshold and definition of income should be checked for the particular tax provision involved rather than assuming every income-based rule works in the same way.
Can pension contributions or Gift Aid affect a client's income thresholds?
Potentially, but it depends on the particular threshold being tested.
Some UK tax rules use adjusted net income, for which certain pension contributions and Gift Aid donations can be relevant. Other rules use a different measure. For example, the Winter Fuel Payment charge is based on total income, with a £35,000 threshold.
Accountants should therefore identify the specific income definition attached to each threshold before advising a client.
What should accountants do if an overpayment relief claim is rejected?
The webinar recommends using a repeatable process for overpayment relief claims and checking that each submission contains the required information.
Where a practice believes a correctly prepared claim has repeatedly been rejected, it should retain the relevant evidence. Persistent problems can then be raised through the appropriate professional or HMRC escalation route.
The webinar's broader practical lesson is to document recurring problems rather than treating every rejected claim as an isolated case.
How can accountants reduce Self Assessment problems before filing?
A useful pre-filing process is to check whether HMRC expects the return, establish whether a previously registered client needs reactivation and collect information that may not appear in standard records.
For 2025/26, that includes paying particular attention to the additional close-company director information and checking Winter Fuel Payment details where relevant.
The aim is to identify missing information and administrative problems before the return reaches the submission stage.
The contents of this article are meant as a guide only and are not a substitute for professional advice. The author/s accept no responsibility for any action taken, or refrained from, as a result of the material contained in this document. Specific advice should be obtained before acting or refraining from acting, in connection with the matters dealt with in this article. The information at the time of publishing was accurate and could be subject to final changes.
