A third of bank branches in Tayside and Fife have closed over the last eight years, according to new research.
Angus and Dundee West were among the worst affected parts of Scotland, losing 15 branches each since 2010.
Campaigners have called for a new regulator to ensure that people still have access to cash amid fears businesses could go under and communities will be cut off.
It comes as 204 of the country’s free-to-use cash machines have been axed in the last year.
Gareth Shaw, head of money Which?, the consumer body that compiled the research, said: “These ongoing closures could have a huge impact on communities across Scotland, stripping millions of people reliant on cash of their ability to go about their daily lives.
“Cash is also a vital backup when digital systems fail – so the UK Government must appoint a regulator to oversee these changes and ensure no-one is shut out from paying for local goods and services.”
There were 190 bank branches in Courier Country in 2010, but that fell by 32% to 130 in 2018, according to the Office for National Statistics.
In the last year alone, at least 17 branches have closed or are due to close in Tayside and Fife, not all of which are included in the Which? research.
The RBS sites that have shut in the last year include Montrose, Pitlochry, Aberfeldy, Dundee Stobswell, Bridge of Allan, Perth South Street, Comrie and Dunblane.
Bank of Scotland has closed branches in Dundee, Lochgelly and Carnoustie, with Kirriemuir also doomed.
Santander is also shutting sites in Brechin, Forfar, Kirkcaldy and St Andrews from May.
Kirstene Hair, the Angus MP, said the loss of 15 branches in her constituency is “extremely regrettable”.
“No community should be cut off in this way and I think the public have a right to expect a basic level of service,” the Scottish Conservative added.
Ged Killen, the Scottish Labour MP, said: “I want to see a revolution in how we regulate access to banking services, with a powerful regulator who can step in when communities are threatened with financial exclusion.”
Kate Forbes, a finance minister in the Scottish Government, has written to the Treasury in support of Which’s campaign for a single regulator.
“The recent loss of free-to-use ATMs, on top of the wave of bank branch closures across the UK, has hit Scotland’s communities and businesses disproportionately hard,” the SNP MSP added.
A Treasury spokesman said: “The decision to open and close branches is a commercial decision taken by the management team of each bank.
“The Government does not intervene in these decisions.
“But we understand the impact that closures can have on communities and people’s jobs.
“Banks must now give customers as much notice as possible when a branch is closing, and ensure they are made aware of the options they have locally to continue to access banking services.”
