The registrar shall allocate to every company a number, which shall be known as the company's registered number.

Companies' registered numbers shall be in such form, consisting of one or more sequences of figures or letters, as the registrar may determine.

The registrar may on adopting a new form of registered number make such changes of existing registered numbers as appear necessary.

A change of a company's registered number has effect from the date on which the company is notified by the registrar of the change.

For a period of three years beginning with that date any requirement to disclose the company's registered number imposed by regulations under section 82 or section 1051 (trading disclosures) is satisfied by the use of either the old number or the new.

In this section “company” includes an overseas company whose particulars have been registered under section 1046, other than a company that appears to the registrar not to be required to register particulars under that section.

The registrar shall allocate to every branch of an overseas company whose particulars are registered under section 1046 a number, which shall be known as the branch's registered number.

Branches' registered numbers shall be in such form, consisting of one or more sequences of figures or letters, as the registrar may determine.

The registrar may on adopting a new form of registered number make such changes of existing registered numbers as appear necessary.

A change of a branch's registered number has effect from the date on which the company is notified by the registrar of the change.

For a period of three years beginning with that date any requirement to disclose the branch's registered number imposed by regulations under section 1051 (trading disclosures) is satisfied by the use of either the old number or the new.