GP practices in north east Lincolnshire have fewer patients on average than almost anywhere else in the country, figures show.
But the British Medical Association said a rapid expansion of the GP workforce across England is needed, as the number of patients per practice hit a new national record.
NHS Digital figures show 170,989 patients were registered at the 25 GP practices in the NHS North East Lincolnshire CCG area, as of the end of June.
This meant each GP team was dealing with an average of 6,840 patients each – though this was up from 6,552 in June 2020.
But that was still one of the lowest averages of all CCGs in the country, and well below NHS Portsmouth CCG, in the South East, where each practice had around 17,699 patients each.
Across England, 60.8 million patients were registered at 6,571 facilities in June – equating to an average of 9,258 people per practice.
This was up 2.4% on a year previously, and the highest figure since comparable quarterly records began in 2015.
Richard Vautrey, chairman of the BMA’s GP committee said: “The differences seen throughout England reflect the overall workforce crisis, which has been troubling for over a decade now.
"Numbers of GPs are falling while demand rises, leaving us with a severe shortage.
"With a growing and ageing population, only a medical workforce expansion will give us hope that we can offer good quality care to everyone in the future.”
He urged the Government to rapidly grow the medical workforce by at least 31% to ensure all citizens receive the same standard of care.
The NHS figures also reveal how one practice in north east Lincolnshire has around 2,968 times as many patients as another.
The Roxton Practice has the most patients registered, with 32,647, while Roxton At Weelsby View has the fewest – 11.
The figures come as new research from the University of Cambridge finds that there are fewer GPs per patient in poorer parts of England compared to wealthier regions.
The academics found that between September 2015 and December 2020 there were, on average, 1.4 fewer full time equivalent GPs per 10,000 patients in the most deprived areas compared to the least deprived areas.
Dr John Ford, the study’s senior author, said: “People who live in disadvantaged regions of England are not only more likely to have long-term health problems, but are likely to find it even more difficult to see a GP and experience worse care when they see a GP.
“This is just one aspect of how disadvantage accumulates for some people leading to poor health and early death."
The Department of Health and Social Care said the new Office for Health Promotion – to be launched later this year – will "level up the health of the nation" and close disparities.
A spokeswoman added: “We have invested £270 million to expand GP capacity, on top of the £1.5 billion for extra staff until 2023-24.
“The highest ever number of doctors accepted a place on GP specialty training in 2020 and we are committed to increasing the number of training places available to 4,000 a year, as well as targeting recruitment in hard-to-recruit areas."