The amount of time it takes to register a company depends on the method that you choose.
Companies are registered via incorporation at Companies House. You can make an application for registration in one of three ways.
Paper filing applications take the longest to process as it involves sending the appropriate documents by post to the required location. Companies House state that straightforward applications will typically be processed within 5 days of them arriving.
This service is available for private limited companies and community interest companies (CIC). Straightforward applications usually take no longer than 24 hours to process.
The speed at which electronic software filing takes place depends on the service you use. Typically, straightforward applications are complete within 24 hours but some services offer a same day guarantee. Web Services