It is possible to add your Company Number, as a limited company, in either the app or the dashboard, in order to include this information in your invoices.
First go to the Settings tab in the Customers/Jobs home page of the app.
then select your account, as below
and enter the "Invoice Settings" section
where you will find the Company Number at the bottom of the page, to insert your company details.
From the dashboard, go to account settings in the top right corner
and select the invoice settings which contain relevant company details that are included in quote and invoices
including the Company number for the limited company.