Keynote monitored 2000 customers as they interacted with 10 online banking sites for the study. In addition to traditional opinion data, Keynote collected qualitative and behavioural information as users performed tasks at each site.

The research found that for 56% of consumers Internet banking and bill payment services were very important when choosing a bank, ahead of considerations such as branch locations (45%) and ATMs (52%).

Keynote says Web banking has continued to climb as a key consideration for consumers, closing in on the two leading factors - free chequing(68%) and service charges (67%).

Customers are also placing greater emphasis on online self-service support. The survey found that 92% of online banking customers use the Web to check transactions, 51% for checking/printing monthly statements and 43% use bill payment services.

Bonny Brown, director of research and public services, Keynote, says as online banking adoption continues it becomes "an increasingly important competitive factor for banks in attracting and keeping customers".

Of the ten Web banking sites evaluated in the study, National City, Washington Mutual and Bank of America (BoA) were found to provide the best online customer experience. Banks were also found to be more successful at driving online adoption, with the Citibank and BoA sites coming top in this category.

But despite the growth in online banking, most banks are still failing to use the Web channel successfully to cross sell or grow their customer base. Keynote says banks perform poorly in cross selling and customers are frustrated with this gap in service. Often information on banking services are not easily accessible when a customer is logged into their banking account.

"Banking customers have continued to express to us their frustrations about being unable to easily find adequate information on additional bank services, such as mortgages and credit cards when they would like it," says Brown.

Performance monitoring firm Keynote acquired Vividence Corporation, which conducted two previous Web usuability studies, in September last year.