Workers in North Devon and Torridge are among the lowest earners in the UK, according to Government figures.
Figures from HM Revenue and Customs show the average worker in North Devon made £19,000 before tax in 2016/17, while Torridge workers fared slightly better, making £19,600.
Both figures are significantly lower than the £23,600 median income across the UK.
In the South West, workers in just four of the region’s 37 authorities earn less than in North Devon: West Somerset (£18,000), South Hams (£18,600), Weymouth and Portland (£18,800) and Cornwall (£18,900).
Workers in Stroud have the highest median salary in the region at £22,800.
Dr Wanda Wyporska, executive director of the Equality Trust, said: “These figures paint a bleak picture for our society, and we can see a huge divide between incomes in the north and the south [of the UK].
“These gaps are further evidence of the shockingly high level of inequality in the UK, which we know is linked to poverty, mental and physical ill-health, and lower levels of social mobility.
“This damages us all, rich and poor.”
Workers in the City of London have the highest median salary in the UK at £54,300, while employees in Boston, Lincolnshire, have the lowest, at just £17,600.
HMRC uses the median, the middle number in a series, instead of the mean average, so the figures are not distorted by extreme highs and lows. The data does not cover people who are self-employed.
The Joseph Rowntree Foundation, a poverty and social mobility charity, urged the Government to focus on strengthening the economies of poorer areas in the UK.
Head of policy and partnerships Katie Schmuecker said: “We all want to live in a society where working hard means being able to improve life for your family, but too many working people are locked in poverty by low pay and high costs. That is not right.
“All parts of the UK need access to the jobs and skills that provide a route out of poverty, and incomes need to match the rising costs which leave many working families struggling to decide which bills they can pay.
“Until work provides a reliable route out of poverty, too many workers will struggle to make ends meet.”