Companies House has published a statement about the security issue which affected its WebFiling service. The issue was identified on Friday 13 March and its WebFiling service was taken offline while it investigated and resolved the problem, which is understood to have been the result of an update to its systems carried out in October 2025. The service has since been restored.

Published: 24 March 2026
Authors: Debbie Brown

Companies House has explained that, during the period in which the issue was live, it was technically possible for a logged in WebFiling user, in limited circumstances, to:

• view certain information not normally shown on the public register, such as dates of birth, residential addresses and company registered email addresses
• make unauthorised filings to another company’s record

At this stage, Companies House has said that it has no confirmed reports of data having been accessed or changed without permission and believes the issue could not have been used to extract data in large volumes. It has also confirmed that:

• WebFiling passwords were not compromised and do not need to be reset
• no identity verification data (such as passport information or personal codes) was accessed
• existing filed documents could not have been altered
• for those persons who have applied under the Companies Act 2006 to protect their personal details, this information was not affected

What companies should do

Whilst the ability to access information and make unauthorised filings is understood only to have been capable of exploitation by a logged in WebFiling user undertaking a particular series of steps, we strongly recommend following the advice which Companies House has issued for all companies to check their registered details and filing history to ensure that the information held on the register is correct and as expected. This can be done using the WebFiling and Find and update company information services.

This issue comes at a time of significant change at Companies House, as reforms continue to enhance the accuracy and transparency of the register. While this issue arose within Companies House’s own systems, its guidance reinforces the importance for companies to actively monitor their records. The free Follow service is a practical tool for this, enabling companies to receive alerts when filings are made, so helping to spot anything unexpected at an early stage.

If anything appears incorrect or unexpected, please get in touch with ShoosmithsCompanySecretarial@shoosmiths.com or your usual contact at Shoosmiths.