by business editor Trevor Sturgess

Sixteen per cent of workers in London and the south east are paid less than the living wage, new research shows today.

While the region has the lowest proportion of sub-living wage earners, there are still 16% of workers across Kent and the region being paid low hourly rates.

And by number - 530,000 - the region has the highest number of workers in this poorly-paid category. The highest proportions are in Northern Ireland (24%) and Wales (23%).

One in five workers in the UK – some 4.8million people – are paid less than the living wage and poor-paying employers have been urged to sign up to more generous rates.

Bar staff, waiters and waitresses, sales and retail assistants are the workers most affected, followed by cleaners, kitchen and catering assistants, launderers and dry cleaners, care assistants and home carers, goods handlers, storage staff, florists and floral designers.

The living wage is a voluntary rate of pay that some employers give their staff, designed to enable workers to afford a basic standard of living. The rate is currently £8.30 an hour in London and £7.20 outside.

This compares to the national minimum wage rate of £6.19 an hour. The research indicates that since 2001, the living wage campaign has benefited more than 10,000 employees and their families, redistributing some £96m to some of the lowest paid workers in the UK.

The research, commissioned from Markit by accounting firm KPMG, comes a few days before the start of Living Wage Week on Sunday, when new rates will be announced.

It shows that in tough economic times of steeply rising food and energy prices, the impact is falling hardest on low-paid workers, with more than four in 10 saying their finances are worse now than they were just a month ago.

Marianne Fallon, head of corporate affairs at KPMG, said: "This research really lays bare the extent of the problem of low pay in Britain.

"Times are difficult for many people, but of course those on the lowest pay are suffering the most. Paying a living wage makes a huge difference to the individuals and their families and yet does not actually cost an employer much more."

Rhys Moore, director of the Living Wage Foundation, said: "Paying a living wage makes a huge difference to the quality of life of thousands of cleaners, caterers and security staff across the country.

"It is really encouraging to see nearly 100 organisations now signed up and accredited. But that still leaves many more organisations that aren't. We hope that Living Wage Week will create real momentum and that many more employers will sign up."