The competition watchdog has begun market investigations into the proposed acquisition of St George Bank Ltd by Westpac Banking Corporation.

Australian Competition and Consumer Commission (ACCC) chairman Graeme Samuel said the organisation is seeking a range of views from competitors, banking customers and other interested parties.

To make the process easier, it has produced two surveys to be filled out by personal banking customers and business banking customers.

Mr Samuel encouraged all banking customers, especially Westpac and St George customers, to take the time to fill out the surveys.

The responses will be used by the ACCC to form opinions about particular markets or issues that may require further investigation.

Banking customers wishing to complete the surveys should visit the ACCC mergers public register website.

Responses should be submitted to the ACCC by June 23.

AAP