England could be facing a shortage of up to 19,000 school leaders by 2022 if action is not taken to plug the gap, it has been claimed.
A report by three education leadership organisations suggests almost one in four schools across the country could be affected by a lack of headteachers, deputy heads and assistant heads.
It argues that an increase in pupil numbers and a rise in school leaders retiring and leaving the profession early along with increasing demand for senior staff to work at academy trusts means that more people are needed to step into top roles.
But currently, many schools are experiencing problems in recruiting staff, the report says, adding that while schools are estimated to spend up to £200 million a year on recruitment, many fail to find the quality of candidate they require.
It concludes that schools in England are battling against:
potential headteachers being put off by the challenges of the job;
the profession lacking a culture of development and feedback;
an inconsistent recruitment of headteachers;
leaders not feeling like they get enough support or motivation to stay.
Overall, England will need between 14,000 and 19,000 more heads, deputy heads and assistant heads by 2022, the report says.
Up to 8,000 may be needed to meet a growth in leadership roles at academy trusts, while there is also a need for 2,000-3,000 more in the current school system. At the same time, the supply of school leaders is expected to fall by 8,000 due to retirement and staff leaving the profession early.
Secondary schools are currently the most affected, but by 2022, the issue will also be having an impact on primaries. Schools teaching the most disadvantaged students are the most likely to be hit by a lack of staff.
The report, by the Future Leaders Trust, Teaching Leaders and Teach First, calls for a new generation of school leaders to be developed by supporting them to move up the career ladder.
It says that more should be done to support school leaders and improve perceptions of the role, and also suggests that the pool of candidates able to take on non-teaching senior roles could be expanded by looking at people outside the profession.
James Toop, chief executive designate of the merging Teaching Leadersand The Future Leaders Trust, said:
A Department for Education spokeswoman said: "We do not recognise these figures. The latest school workforce data shows that there are 68,800 FTE leaders in state schools in England. Furthermore, since 2010 the proportion of schools reporting a headteacher vacancy has decreased and the number of school leaders over the age of 50 has decreased significantly.
"However, we recognise that we need to work with the profession to ensure we can develop even more great school leaders. We are doing this through a range of professional training including the National Professional Qualifications, the High Potential Middle Leaders and High Potential Senior Leaders programmes to develop excellent leaders in challenging schools.
"We are also continuing to support the expansion of Teach First to recruit more top graduates with the potential to become future school leaders in some of the most challenging parts of the country."