The bank said it would also upgrade its mobile platforms and roll out wireless service and other new technology, like iPads to log onto its online banking network, at 400 of its branches.
RBS said it expected about half of its customer transactions to come from its mobile applications in the next four years, up from about 40 percent in 2013. Branch transactions are expected to account for only about 5 percent of its business by 2017, compared with 13 percent last year.
"Our customers' needs are rapidly changing," said Les Matheson, the chief executive of RBS' personal and business banking operations. "We must respond to their needs and continue to improve on the service we offer both online and on mobile."
RBS has acknowledged that it will probably close some branches over time as consumer habits change but that its branch network remains an important access point for its customers - whether for transactions or financial advice.
At the company's annual meeting Wednesday, Philip Hampton, the RBS chairman, said, "There will inevitably be further closures" as consumers rapidly change the way they bank.
RBS said customers' use of online and mobile technology has grown by more than 200 percent in the past three years.
The digital-focused strategy comes as Ross McEwan, the bank's chief executive, has said he is trying to reshape RBS from a lender with vast international ambitions to a "a smaller, simpler and smarter bank."
RBS, which is 81 percent owned by the British government, is shifting its focus to primarily the British retail and commercial market. It is also selling or spinning off several businesses, including its Citizens Financial Group in the United States.