No teachers have been fired for incompetence in almost half the local authorities in England during the past five years, figures from a TES investigation have revealed.
Nationally, more than 3,200 teachers have gone through official competency procedures over the same period, figures collated for the first time reveal.
This resulted in 273 teachers being fired or accepting severance pay and leaving, but in 72 local authorities there are no records of any teachers being removed from their posts.
The figures highlight the enormous variations in how local authorities deal with underperforming teachers.
In West Sussex, 385 teachers were subjected to competency proceedings, compared to just one teacher in four other councils.
The TES figures are from 123 of England's 152 local councils, providing the most comprehensive picture to date of teachers being identified as substandard and the action taken against them.
Poorly performing school staff have received more than pound;2.3 million in severance packages and compromise agreements in the same five-year period, freedom of information requests have uncovered.
They come as the Department for Education announced this week that it plans to overhaul the rules governing performance management of teachers within a year.
Competency proceedings are only supposed to begin when regular performance management has failed to improve teaching standards to a satisfactory level.
Chris Keates, general secretary of the NASUWT, said that the union was receiving growing numbers of complaints that the process was being abused. "Heads are using it as a blunt instrument for inappropriate reasons," she said. "We get many reports that it's just an excuse for bullying."
But Russell Hobby, general secretary of heads' union the NAHT, has called for the system to be streamlined so that it is possible to fire incompetent teachers within eight weeks.
"I don't think there is a massive group of dire teachers out there, but there are people who should not be teaching and they need to be dealt with as quickly as possible," he said.
Chris Woodhead, former Ofsted chief inspector, created a storm 15 years ago when he said that there were 15,000 incompetent teachers, out of a workforce of around 500,000.
Commenting on the TES findings, Professor Woodhead said: "This is a tiny percentage of the total workforce. It confirms, moreover, what we all know: incompetence pays.
"Incompetent teachers damage children's learning and the reputation of the teaching profession. When are those responsible going to face up to the problem?"
Teachers suspected of serious incompetence who leave their jobs are supposed to be reported to the General Teaching Council for England, but figures show that only a small proportion of cases are passed on.
Keith Bartley, GTC chief executive, said: "The TES research confirms that some local authorities appear to be failing in their statutory duty to refer cases of serious professional incompetence."
A spokesman for the Department for Education said: "The vast majority of teachers in our schools are highly competent professionals who are committed to providing a good education for our children. But where teachers do not meet the standards expected, it is important that heads have the freedoms they need to tackle underperformance."