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United KingdomGOV.UK

OS CH01 address must be the UK establishment's physical location

OS CH01 filers must enter the physical UK location where the establishment carries on business, consistent with the address particular required by regulation 7.

By Taxxa AI OyPublished 25 September 2026

Legal & Corporate

An overseas company filing form OS CH01 to change the details of a UK establishment must give the UK establishment addressGOV, meaning the physical location in the United Kingdom where the company carries out its businessGOV. That definition now appears on the GOV.UK page for the formGOV, alongside the existing instruction to use only entries from the standard nationalities and countries list when completing nationality fields.

OS CH01 is the return a UK establishment of an overseas company uses to notify a change of details. The address instruction is new against the previous version of the page, which gave only the form's purpose and the nationalities-list directionGOV. In substance it pins the address field to the place where the business is actually carried on in the UK, rather than any other address connected with the company, such as an overseas registered office or a separate service address.GOV

The underlying register rule supports that reading. Regulation 7 of the Overseas Companies Regulations 2009 lists the particulars of the establishment that the return must include: the address of the establishment, the date on which it was opened, the business carried on at it, and the name of the establishment if different from the name of the company.Legislation The return must also name every person resident in the United Kingdom authorised to accept service of documents on behalf of the company in respect of the establishment, or state that there is no such person, and list every permanent representative with name, former names, service address and usual residential address. The address of the establishment has therefore always been a required particular; the page now tells filers what address that means in practice.

For company secretarial teams and formation agents, the practical point is a pre-filing check: the address entered on OS CH01 should be the UK premises where the establishment operatesGOV. Where a company operates from more than one UK site, the filer should identify which establishment the return relates to and give that establishment's address, A registered-office address abroad, a correspondence address, or the service address of a person authorised to accept documents does not satisfy the field.GOV

The remainder of the page is unchanged: nationality and country entries must still come from the published standard list, and the form remains the route for establishment-level changes rather than company-level changes, for which the OS CH02 form applies.

Legal basis: Overseas Companies Regulations 2009 reg 7, as reflected in the GOV.UK guidance page "Change the details of a UK establishment of an overseas company (OS CH01)".

Before filing OS CH01, check the address entered is the physical UK location where the establishment carries on business, and use OS CH02 for company-level changes rather than establishment-level ones.

Sources