'Customers won't notice any difference'
More than 600 new standalone TSB branches opened on Monday morning following a split from the Lloyds brand.
Five million customers are seeing their accounts automatically transferred from Lloyds to TSB.
Customers' bank account numbers and sort codes will remain the same.
BBC Breakfast's Dominic Laurie visited one of the new branches in Wilmslow, Cheshire.
Lindsay Thomson from TSB told him existing customers would not notice any difference and "we know we're attracting new customers daily".
However, personal finance journalist Sarah Pennells said: "All the banks are competing for new customers... I think there could be a bit of a struggle because some of the banks have got very attractive deals".