A registered office is a legal requirement for all companies registered with Companies House. It is the official address of the incorporated company and is accessible to the public. The address may be different from your usual business address. Companies House, HMRC and other government bodies will use your registered office address to send statutory letters and legal notices. All companies are legally obliged to display the registered office address on business correspondence such as letters and the company website.
For further information:
https://www.gov.uk/limited-company-formation/company-address