Santander says it has brought its call centres back to the UK from India following complaints.
Chief executive Ana Botin told the BBC customers had said it was "the most important factor in terms of the satisfaction with the bank".
It is taking on 500 staff for new phone centres. The bank has 25 million customers and 1,300 branches in the UK.
The bank acquired Abbey, Alliance & Leicester and parts of Bradford & Bingley in 2008.
Commenting on the call centre move, Ms Botin said: "This is what our customers have told us is the most important factor in terms of the satisfaction with the bank, and we have listened to them and decided to bring all of our retail call centres back from India."
BBC personal finance correspondent Simon Gompertz said Spanish bank Santander had one of the worst complaints records in the industry last year.
Our correspondent also said there was a trend for banks and other companies to bring call centres back to the UK, although many are now moving administration work to cheaper countries instead.
On Tuesday, telecommunications company New Call Telecom announced that it was moving one of its call centres from India to Lancashire, in a move that is expected to bring 100 jobs to the area.
New Call Telecom transferred its business to Mumbai three years ago, but increased costs has prompted it to move to Burnley.
The company highlighted a growing trend in India for higher costs of property, salaries and accommodation.
In September 2010, Santander said it was creating 400 call centre jobs in the UK following rapid growth in its business.
Liverpool got 200 of the call centre jobs, with 100 in both Leicester and Glasgow.