HSBC has said it will launch a robo-advice service next year.
Dean Butler, the bank's head of retail wealth, said it represented a "tremendous" opportunity for HSBC to service its customers through their entire life cycle.
Speaking at the Boring Money Fin-K Tank event yesterday (6 December) at a panel session involving Nationwide and Santander as well, he said: "As a business over the past two years we have undergone a significant change. We are now coming a fully fledged digital organisation.
"We have more than 26 million customers who sit on cash savings [between HSBC, Santander and Nationwide]. That is more than Hargreaves Lansdown and using data by talking to our customers we can see what they want.
"We have more than three million customers who are basically ripe for this proposition. It is a true advice proposition that tells you how long you should invest for and what wrapper you should have.
"The opportunity is big but we have got to get this right and we have got to make this right through education. I don't think we can do this by ourselves."
Hargreaves Lansdown, which describes itself as the UK's "number one" investment supermarket for private investors, has £82bn under management from 983,000 clients.
Last month NatWest launched its robo-advice service and earlier this week it was revealed Nationwide would be testing a digital investment advice service in the Financial Conduct Authority's regulatory sandbox.
The regulator confirmed Nationwide will be testing an automated solution providing digital savings guidance and investment advice.
Steven King, product manager for investments at Nationwide, said the service would not be aimed at all the building society's customers.
He said: "We have a responsibility to make sure they are in the most appropriate products there are to suit their needs.
"This is about making sure we are basing a recommendation on their personal circumstances. It is as important to tell them not to invest as it is to do so."