Mobile banking on phones and tablets will become more popular than internet banking on computers next year, a report predicts.
At present, 41% of current account holders are likely to use mobile banking on a regular basis while 42% are likely to use internet banking on their computer, according to the findings.
By 2019, 47% of current account holders will be likely to use mobile banking on a regular basis while 36% will be likely to use their computer regularly to manage their current account, the report predicts.
Changes in behaviour by older people are driving the changes, the research said.
CACI said on average, people now visit their bank branch only five times per year.
Rural areas and coastal towns are likely to see a particularly big jump in digital banking, CACI predicts.
Jamie Morawiec, associate partner at CACI, said: "It's clear that the first wave of digital banking migration has taken place in the UK and what we will see in the next five years is a different demographic driving digital growth.
"At the moment, rural areas and coastal towns have low levels of digital channel use.
"This contrasts with large urban areas, which already have much higher numbers of mobile users.
"Almost half of customers in places like London, Oxford and Brighton are already using apps to manage their current accounts."
The findings come as bank branch numbers dwindle.
Earlier this month, Royal Bank of Scotland said it is to close 162 branches in England and Wales.
In April, Lloyds Banking Group outlined plans to shut 49 branches.