MOBILE banking transactions are booming with the National Australia Bank reporting 2.1 million transactions from mobile browsers and apps for the month of July at a value of about $1.5 billion.

The bank's mobile banking transaction rate is growing at 10 per cent a month, according to Ben Forsyth, NAB's head of mobile technologies.

The bank estimates some 36 per cent of logins to internet banking last month were from mobile devices and of those logins, 80 per cent were from smartphone apps with the rest coming from browsers.

NAB general manager of digital, Chris Smith, expects that half of internet banking logins will be from mobile devices next year.