An independent review has been set up to examine the impact and implications of using new technology to make payments over the course of the next five to 15 years.
The Access to Cash Review will look at the effect of increasing contactless card and digital payments on consumers and small businesses, and review the evidence on future trends in cash usage and ATM coverage.
A call for evidence has been issued and will remain open until 30 September 2018.
Natalie Ceeney, former head of the Financial Ombudsman Service, who is leading the review, said: The rise of contactless and digital payments has changed the relationship between cash and consumers.
Many people in the UK have already made a shift to paying for most things digitally, but at the same time, there are between two and three million people across the UK who are entirely reliant on cash.
Initial findings suggest that around 4% of UK adults relied almost entirely on cash payments in 2017, while almost 6% of UK adults made cash payments once a month or less.
Harry Rose, money editor of Which?, commented: We ve seen hundreds of ATMs closing across the country, with more under threat, which risks excluding the millions of people still reliant on cash in their daily lives.
The review will gather information from consumer groups, community representatives, small businesses, industry and the general public, and will produce a final report in the first half of next year.