Barclays is offering triple overtime pay to frontline staff as it tries to manage an “unprecedented” surge in demand for mortgage holidays and government-backed business loans during the coronavirus lockdown.

The move will affect thousands of lower-paid employees in call centres and branches who are working extra hours to deal with an increase in customer calls and a jump in the number of colleagues off work because they are ill, self-isolating or juggling childcare. It is understood that up to 30% of Barclays’ key staff have been unable to work at any one time during the outbreak.

The government and regulators have put banks on the frontline of historic stimulus measures, which include billions of pounds’ worth of low-cost loans to UK businesses, mortgage holidays for households and extending credit card limits for consumers. Last week, the chancellor, Rishi Sunak, said there had been 30,000 inquiries to banks about the coronavirus business interruption loans scheme in just four days.

In an internal memo sent to key workers, Barclays said: “We’ve been looking at ways we can help manage the unprecedented operational volumes we’re seeing at this difficult time – one of those is increasing the overtime hourly rate.”

The memo explains that overtime will be paid at “three times their hourly rate”, covering contractors and local managers who are not currently eligible for overtime pay. While some of Barclays’ investment bankers are considered key workers, they are not part of the overtime scheme.

The Guardian understands that the average salary for a full-time call centre worker in the UK can average between £18,000 and £25,000 per year, depending on their job title and the amount of time they’ve been employed.

The Barclays payout comes after some US banks said they would increase payouts for employees who could not work from home during the outbreak. JP Morgan said it would give workers a special payment of $1,000 each (£800), while Bank of America promised to give frontline staff an extra $400 per month. Wells Fargo has offered similar benefits for its workers.

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But some UK banks have been hesitant to follow suit. One source has said there are concerns about finding the right balance between compensating staff and ensuring they are not being incentivised to work if they are unwell or caring for vulnerable family members.

The Unite union, which represents Barclays workers in call centres and branches, welcomed the hike in pay for frontline staff. However, it warned that Barclays was falling short in areas such as maintaining social distancing and keeping branches open on Saturdays when most high street branches have started to close on weekends.

Barclays said it was keeping the branch opening hours under review.

Barclays said: “Our colleagues are our number one priority and we hugely appreciate the extraordinary efforts they are making to provide essential services, especially for our vulnerable customers during this unprecedented period of time.”

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