From 13 October 2025, customers will need to use GOV.UK One Login to sign in to their Companies House WebFiling account, says a recent Companies House communication.
This is part of a move for unified and secure gov.uk services, and you can find out more with the link https://www.gov.uk/government/news/access-to-companies-house-webfiling-accounts-to-move-to-govuk-one-login.