Banks are increasingly targeting their current account customers with special deals on other products including mortgages, according to Defaqto.
It believes the sector is increasingly trying to build strong relationships with its customer base.
Halifax is the latest to join the trend. It offers between 0.2% and 0.4% off certain mortgages to current account customers.
Defaqto says banks see the current account as the main relationship builder with the customer and it also enables them to have a much better understanding of the financial capabilities of each customer.
The financial information provider added that the cross-selling of other products on to the existing customer base is destined to become the key battleground as each bank strives to become the one-stop shop for all the personal finance needs of their customers.
The practice is likely to lead to banks taking advantage of their existing relationships to sell products currently sold by IFAs.
David Black, banking specialist at Defaqto, said: "We have already seen banks focussing their unsecured lending on their existing customers but now there is the beginning of a trend to target mortgage lending in the same way with a series of special mortgage offers available exclusively to current account customers."
Abbey offer its Zero Current Account exclusively to their mortgage customers. It offers free valuations and a cash back on certain mortgages to their Abbey or Alliance & Leicester current account customers.
Nationwide offers 90% mortgages to their FlexAccount customers and NatWest gives some preferential mortgage rates to their Advantage Private, Advantage Business and Advantage Gold current account customers.
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