With cash no longer king, and electronic payments on the rise, there is less and less of the spare change that homeless people and many charities rely on around.

But the Big Issue has announced plans to embrace the technological change, and hopefully boost its homeless vendors’ income, by issuing them with card readers.

Instead of digging at the bottom of their pockets for notes and coins, potential purchasers will be able to just tap to pay for their magazine.

The eight-week trial, beginning on Monday in London, Bath, Birmingham, Bristol and Nottingham, is a response to figures showing cash payments in steep decline – falling from 62% of transactions in the UK in 2006 to 40% last year.

They are expected to decline further to 21% by 2026. Last year Barclaycard warned that charities may be missing out on more than £80m each year by only accepting cash donations.

Russell Blackman, managing director of the Big Issue, said: “Obviously, we’re moving swiftly towards a cashless society. In the last few years, Big Issue sellers have been proactive and they’ve gone off and purchased their own payment devices, but we hope this pilot is the starting point that will provide more vendors with an income in the changing landscape.”

Big Issue vendors, Easton Christian, Emma Ford, Paul Logan and Mary Holden, who will now be able to offer their customers the option to pay for the magazine by card. Photograph: Louise Haywood-Schiefer/PA

If the trial goes smoothly, it will be rolled out nationally, although it will not be simple. To have a card reader, a vendor must have a bank account, which requires a fixed address. As a result, the pilot has been limited to 20 sellers and, if it is to be expanded, Big Issue will have to work with vendors and banks to help them open accounts.

One of those participating in the trial, Paul Logan, 59, who sells the magazine in Bristol, said people often told him they were not carrying cash, although it was sometimes difficult to tell whether they were just making an excuse.

“People comment: ‘Don’t you have a method where I can pay by card, that would be easier and more people would be able to buy it,’” he said. “It can only help if they see that I can offer them an option. I think it most definitely should increase the money I get. I’ll just have to shout out: ‘We take debit cards and credit cards.’”

Big Issue vendor, Kris Owen, with his new iZettle card reader. Photograph: Francesca Stone/PA

Another trial participant, Easton Christian, 64, who sells the magazine at White City, London, said he had “definitely noticed a dip in the number of people carrying cash, which has had a knock-on effect on the number of magazines that I’m able to sell”.

Other social enterprises and charities have also been exploring ways to ensure they do not miss out as a result of the dash away from cash.

Earlier this year, Greater Change was launched in Oxford, which allowed passersby to donate to homeless people via an app by scanning a barcode worn around the individual’s neck. In the Netherlands, the Helpless Heart contactless jacket trial last year allowed passersby to donate by tapping a card on the chest of the homeless person’s coat.

In the US, the newspaper Street Scene launched an app last year to enable homeless vendors to take cashless payments, and collect the money from the offices at the end of the day. In Sweden, Situation Sthlm, also a newspaper sold by homeless people, has teamed up with the same card reader company – iZettle - as the Big Issue.

Tap London ran a pilot scheme earlier this year that allowed homeless vendors carrying contactless card readers to raise money for homeless charities, while being paid the living wage, by selling cards designed by local artists.

On Wednesday, the social enterprise launched an initiative, backed by Sadiq Khan, allowing people to donate £3 at contactless points around the capital to help tackle homelessness, which has already had more than 1,000 taps.

Katie Whitlock, co-founder of Tap London, said: “People really want to give and we’re not carrying much change anymore, and it’s having a detrimental effect on people and charities, and that’s beyond homelessness.

“Hearing the Big Issue is planning to do the same [go contactless], we’re really thrilled, hopefully it will make a big difference to their vendors. The UK’s been waiting for this.”