I'm with the HSBC, I have two current accounts. Both personal accounts not business. 1 used for personal, 1 used for business. My bank know I use it for business, they think I am a Masseusse legit lol. I even have credit card payments from my card reader paid in regularly. My weekly wages are paid in one large chunk each week in cash by myself. I have had a few issues with being paid in fake notes. Which the bank helped me with paperwork for my accountant. Still not an issue.
I have even had a lengthy compliance investigation with HMRC which my bank complied with. Never have they questioned my account. I did ask them if I needed a seperate business account and they said it was not necessary.
My accountant doesn't like me doing this, he wants a business account. But seeing as having a business account only costs me money and doesn't offer me any privacy with my personal account from HMRC, I just don't see the benefit.
But my bank also see me paying my tax each month, so maybe that's why I been left alone as they know I paying taxes.