One in 10 people have been refused by shops when trying to pay in cash during the lockdown, according to Which?
The consumer group said it is concerned the coronavirus crisis is accelerating a shift towards a cashless society, potentially leaving vulnerable people without a "payment lifeline" for essentials.
When asked, 10% of people said that, since the lockdown restrictions started, they had been turned down by shops when trying to pay for items with banknotes and coins.
Just over a quarter (26%) said they were left unable to make their purchase on at least one occasion as they had no other way of paying.
One in 14 (7%) people have found it harder to take out cash since the coronavirus pandemic started.
John Crossley, head of money at comparethemarket.com, said: “The UK is increasingly heading towards a cashless society.
"COVID-19 has undoubtedly accelerated this long-term trend, with the spending limit for contactless payments increasing from £30 and £45 at the start of April and many shops encouraging the payment for goods with cards instead of cash."
But that is far from a good thing for some people.
“In the rush to ditch notes and coins for plastic, it is important that the banking sector caters for those who do rely on cash for everyday living, including paying bills," Crossley sad.
"Cash remains a lifeline for some elderly and vulnerable people, and it is important that cash remains accessible for those who wish to continue using it.”
Which? said that, with many retailers encouraging non-cash payments, and banks having reduced branch opening hours, it wants to see action to ensure millions of people who rely on cash are not left abandoned.
Gareth Shaw, head of money at Which?, said: "The coronavirus outbreak has shown that cash remains vital to many consumers, particularly for vulnerable people who rely on it to pay for essential supplies.
"As a result, it's vital that the already fragile cash system is not left to collapse completely as the UK's shift to a cashless society accelerates.
"The Government must urgently press ahead with the legislation it has already committed to before it becomes obsolete, as failure to do so risks excluding millions of people from engaging in the economy."
Caroline Abrahams, charity director at Age UK, said: "It's deeply worrying that some older people are telling us that they are finding it so hard to access cash and how worried they are about how they will pay for their shopping, and are concerned their supplies of essentials will run out soon if they have no means of paying for more."
She said making sure older people have the coins and banknotes they need to keep spending is "surely in the best interests of businesses and the economy too".
She continued: "Before the pandemic started the Government committed to legislating to protect access to cash for as long as people need it and this must happen sooner rather than later."
