A Companies House blunder has raised concerns after a flaw in the WebFiling service briefly exposed sensitive company data. The issue, identified on 13 March 2026, meant that a logged-in user could potentially access and amend limited details of another company by carrying out a specific sequence of actions.

Companies House has stated that this system vulnerability was not available to the general public. Only users with authorised access codes who were already logged into the system could have exploited it. Nevertheless, the nature of the flaw meant that certain private information, such as dates of birth, residential addresses and company email addresses may have been visible. There was also a risk that unauthorised filings, including accounts and changes to director details, could have been submitted on another company’s record.

After identifying this issue, Companies House shut down the WebFiling service at 13:30 on 13 March to investigate. Following independent testing, the system was restored at 09:00 on 16 March. Companies House has said that passwords and identity verification data were not compromised, and that existing filed documents, such as accounts or confirmation statements, could not be altered.

The issue is believed to have arisen from a WebFiling systems update in October 2025. It has been reported to both the Information Commissioner’s Office and the National Cyber Security Centre.

Companies are now being urged to review their registered details and filing history carefully. While no confirmed misuse has been reported so far, Companies House is continuing to investigate. If a company has a concern, it should raise a complaint via the Companies House complaints page at www.gov.uk/government/organisations/companies-house/about/complaints-procedure and include evidence to describe the issue.

If you have not yet checked whether you need to use Making Tax Digital (MTD) for Income Tax, now is the time to urgently see if you are affected. The Income Tax reporting requirements for some self-employed individuals and landlords will change significantly from 6 April 2026. MTD for Income Tax changes the traditional annual self-assessment process to a new digital record-keeping and quarterly updates process submitted through recognised software.

From April 2026, those with qualifying income over £50,000 will be required to maintain digital records and submit quarterly updates of trading or property income and expenses. From April 2027, the threshold will reduce to £30,000, and in April 2028 it will further reduce to £20,000. 

A full tax return will still be required by the following 31 January after the tax year i.e. the first MTD for Income Tax return, covering the 2026-27 tax year, will be due by 31 January 2028.

MTD aims to reduce errors, improve efficiency, and support business productivity. HMRC estimates that around 860,000 taxpayers will join in 2026, with more joining in 2027. 

The system also provides exemptions for those unable to go digital and offers accessible software solutions. Taxpayers joining MTD for Income Tax in April 2026 will not receive penalty points for late quarterly updates for the first 12 months. This will allow them time to adapt to the new system.

1 April 2026 – Due date for corporation tax due for the year ended 30 June 2025.

19 April 2026 – PAYE and NIC deductions due for month ended 5 April 2026 (If you pay your tax electronically the due date is 22 April 2026).

19 April 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 April 2026.

19 April 2026 – CIS tax deducted for the month ended 5 April 2026 is payable by today.

30 April 2026 – 2024-25 tax returns filed after this date will be subject to an additional £10 per day late filing penalty for a maximum of 90 days.

1 May 2026 – Due date for corporation tax due for the year ended 30 July 2025.

19 May 2026 – PAYE and NIC deductions due for month ended 5 May 2026. (If you pay your tax electronically the due date is 22 May 2026).

19 May 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 May 2026.

19 May 2026 – CIS tax deducted for the month ended 5 May 2026 is payable by today.

31 May 2026 – Ensure all employees have been given their P60s for the 2025/26 tax year.

External risks can affect even well managed businesses. Many threats arise outside the control of business owners, yet they can have a significant impact on profitability, cash flow and long term stability. Economic change, regulatory developments, market disruption and supply chain pressures can all create uncertainty. Forward planning allows businesses to prepare for these risks and respond with greater confidence.

Economic uncertainty

Changes in interest rates, inflation levels and consumer demand can quickly alter trading conditions. Rising costs may reduce margins, while reduced customer spending may affect turnover. Businesses that monitor economic trends and prepare financial forecasts are better placed to identify pressures early. Planning allows time to review pricing policies, reduce unnecessary expenditure and strengthen cash reserves where appropriate.

Legislative and regulatory change

Tax legislation, employment law and compliance requirements frequently evolve. Businesses that do not keep pace with change may face unexpected costs or administrative burdens. Examples include developments in Making Tax Digital, changes to employment rights, or adjustments to tax reliefs and allowances.

Planning enables businesses to anticipate regulatory developments and assess the likely financial impact. Early preparation reduces disruption and allows time to consider alternative structures or processes where appropriate.

Supply chain disruption

Recent global events have demonstrated how supply chains can be affected by political tensions, transportation difficulties and shortages of key materials. Businesses reliant on a limited number of suppliers may face delays or increased costs.

Contingency planning may include identifying alternative suppliers, reviewing stock levels or renegotiating delivery arrangements. Diversifying supply sources can improve resilience and reduce dependency on any single provider.

Technology and market disruption

Technological change continues to reshape many industries. New entrants, digital platforms and automation can alter customer expectations and competitive pressures. Businesses that review their market position regularly are better placed to identify opportunities as well as risks.

Planning may involve investment in systems, staff training or revised marketing approaches. Understanding customer needs and monitoring competitor activity supports more informed decision making.

Cash flow pressure

Cash flow remains one of the most common causes of business difficulty. External factors such as rising costs or delayed customer payments can place strain on working capital.

Preparing cash flow forecasts allows businesses to anticipate shortfalls and consider funding options where required. Early discussions with lenders or advisers can provide greater flexibility than reactive decision making.

Conclusion

External threats are an unavoidable aspect of running a business. While risks cannot always be prevented, their impact can often be reduced through careful planning. Regular review of financial performance, regulatory developments and market conditions helps businesses respond more effectively to change.

A structured planning approach supports resilience and improves the ability to make timely decisions. Businesses that take time to assess potential risks are often better positioned to maintain stability and identify opportunities for sustainable growth.