Two out of every 31 NHS operations has a waiting time of more than six months for patients in Dacorum.
That is according to new figures, which show that in May 2019, waiting times for 5,280 operations were more than 26 weeks – or 6.4 per cent.
And one out of every seven patients, or 14.1 per cent – had to wait longer than the NHS target of 18 weeks.
Health campaigners said the figures showed why more investment was needed in local health services.
Edie Glatter, from the Dacorum Hospital Action Group, (DHAG) said: “This is a real problem that has a serious impact upon people’s health and well-being.
“Waiting for a procedure like a hip operation or cataracts can be very painful, and a longer wait can mean the condition deteriorates.”
The figures were collected by The Independent Healthcare Providers Network, which represents a range of private healthcare firms.
They show a huge range between different parts of the country.
Just 1.6 per cent of operations – or one in 63 had a waiting time of 26 weeks or longer in Barnsley.
But in Brighton and Hove more than a quarter (26.4 per cent) waited 18 weeks or more, and around one in seven – 15.3 per cent – had a wait of 26 weeks or longer.
According to NHS guidelines the target is that patients should wait 18 weeks or less for their operation.
People waiting over six months for their procedure should be specifically contacted and given the option of faster treatment at an alternative provider.
Mrs Glatter said this reflected the wider issue of the NHS needing more investment, pointing locally to the campaign for a new hospital for West Hertfordshire.
She added: “We desperately need a new hospital that is fit for the 21st century.
“It won’t solve all of the problems we have, but it is absolutely crucial to doing so.
“The government has announced new funding for the NHS this week and that is welcome.”
Herts Valleys Clinical Commissioning Group, which oversees healthcare across the area including Dacorum, was unavailable for comment.