Why one is effectively essential
A separate account is how you evidence that company money belongs to the company and not to you personally, which matters for limited liability, for corporation tax computations, and for any HMRC enquiry into director's loans or benefits in kind.
Suppliers, payment processors and customers also expect payment to and from a business account in the company's name; an account held in a director's personal name or an overseas entity's name looks irregular and can slow down commercial relationships.






