Alliance & Leicester will create a single view of customers across all communication channels.
C&W will help the bank integrate six Alliance & Leicester call centres to one virtual contact centre in a five-year deal designed to enhance customer service.
The bank will use C&W's network and call routing technology to route calls to the right call centre. The system will be rolled out over the next 18 months.
Sophisticated call-routing technology is becoming widely used in Europe as it allows companies to cut costs and improve customer service, analysts said.
Alliance & Leicester manufacturing and operations director Chris Rhodes said, "Our strategy is to create a single view of our customers across all communications channels. However and whenever we communicate with our customers we can provide the best service level."
The contact centre will use C&W's network to handle the initial call and verify the customer's identity before routing it to the relevant call-
It will use C&W's Network Interactive Voice Response and Network Computer Telephony Integration technology.
Steve Blood, research director at IT analyst Gartner, said call distribution technology was a wise investment for firms with scattered call centres. "It's a practical technology and will help the bank cut costs and improve customer service," he said.
The centre will require a link between C&W's network and Alliance & Leicester's back-office systems, which store customer information," he added. This would normally be done through a virtual private network.
Alliance & Leicester refused to comment on the implementation details.