Average earnings for a college chief executive rose from pound;86,000 in 2003 to pound;106,000 last year - a rise of 23 per cent.

The news comes as the six unions representing staff at all levels in FE put in a claim for a 6 per cent pay rise, despite funding uncertainty. With an average increase of 22 per cent over a decade, the unions argued that salary rises for lecturers and managers had lagged far behind both the public sector and private companies.

Pay in the public sector has risen by more than 41 per cent over the past 10 years, suggesting that the increases for principals have been in line with the rest of the economy.

The highest paid principal, earning pound;184,000 a year, is Jackie Fisher at Newcastle College, where rapid expansion, mergers and acquisitions have also led to the largest turnover - pound;115 million.

Ms Fisher declined to comment.

Comparisons compiled by Income Data Services show that an NHS trust job with similar responsibilities would typically command about pound;132,000, while the chief executive of a private company of that size would earn about pound;350,000.

Five years ago, just two principals earned more than pound;150,000 a year: now the figure stands at 13, while the number of six-figure salaries has nearly doubled, from 102 to 202.

Barry Lovejoy, head of further education at the University and College Union, denied that it was unreasonable to expect a significant pay rise for FE staff despite the recession and uncertainty over funding. “Does the same question apply to senior post-holders?” he said.