The living wage - currently calculated at £7.85 - is based on the amount an individual needs to earn to cover the basic costs of living.
Woking has the highest proportion of people paid below it, at 38%, following by Rother at 37% and Thanet at 36%.
The research was done on behalf of accountancy firm KPMG.
38% Woking
37% Rother
36% Thanet
33% Wealden
32% Arun
The minimum wage is £6.70 per hour, which will rise by 50p in April.
Speaking to BBC Inside Out, Sarah Vero, who is the director of the Living Wage Foundation, said the new rate was not a "living wage".
"The government's new national minimum wage is exciting because it means six million people are going to get a pay rise in April 2016," she said.
"However, our rate [at £7.85] is slightly higher and it's calculated according to the cost of living in the UK, so it takes into account a basket of goods, food, housing, transport, child care and it puts that into a calculation and says what's the basic but affordable standard of living you need."
£7.85
Living wage rate
£9.15
London living wage rate
£7.20 The Governments National Living Wage rate
Gemma Stacey, from Ramsgate, who works part-time in sales and has two children, said she was struggling on low wages.
She said: "I try to make sure the kids eat healthily but sometimes you just can't, sometimes you haven't got the money that week to buy proper food.
"I don't want [my children] to grow up seeing me at home trying to find a job and struggling... I want them just to look up to me and be proud."
The South East as a whole has the lowest proportion of people being paid below the living wage - currently 19% compared to a 23% national average.
However, there are concerns the government's planned tax credit cuts will hit low-paid families hard.
Craig Mackinlay, the Conservative MP for South Thanet, said: "I know it's tough, you know the easiest thing in the world is to do nothing and just say we will keep on paying because it's all too difficult.
"We've been elected on a promise of getting the benefits bill down, on a promise of getting the nation's finances back in order and that's what we're doing."
Inside Out is broadcast on BBC One on Monday, 2 November at 19:30 GMT and nationwide for 30 days thereafter on the iPlayer
Nearly one in five people working in the South East earns below the living wage, research has revealed.