Men who do a Masters degree in English earn 30 per cent less than if they had not by their mid-30s, the Institute for Fiscal Studies has found.
Some postgraduate courses – such as law, business and economics – generate a positive return just over a decade later, according to research commissioned by the Department for Education (DfE).
Men and women who studied these courses earn up to 25 per cent more by the time they are aged 35 than if they had not taken them.
But a large number of arts and humanities postgraduate courses leave both male and female graduates worse off, including languages, creative arts and history where earnings can be over 20 per cent less.
Having done an arts undergraduate degree, “doubling down” by going on to a masters in the same field seems to result in large negative returns, the report said.
The IFS analysis is based on the Longitudinal Education Outcomes data which links the university and tax records of everyone in England who has done a degree since 1995.
The research was commissioned by the DfE who wanted to investigate the effect of postgraduate degrees on future earnings.
More than 350,000 students now start a postgraduate course in the UK each year, compared to only around half this number two decades ago.
Overall, male and female postgraduates in the UK enjoy an earnings boost by the age of 35 compared with those with only an undergraduate degree.
But the financial returns for postgraduate qualifications are negative for men when they are compared with those with similar prior attainment and background, researchers found.
Male masters graduates earn £55,800 on average by 35 which £5,000 more than those with just an undergraduate degree. But most of these differences can be accounted for by the cohort coming from “better-off backgrounds” and having “higher prior attainment” than those who just do degrees, they said.
Laura van der Erve, one of the report’s authors, said that while some postgraduate courses can “substantially boost” earnings, others appear to do the opposite.
“On average, masters graduates do not see substantially higher earnings than otherwise-similar individuals who don’t go beyond undergraduate level,” she said. “However, this obscures huge differences across subjects.”
For students with an undergraduate degree in economics, law and many science subjects, PGCE teaching qualifications reduce earnings by more than 10 per cent.
These patterns may explain teacher recruitment challenges in subjects such as maths, physics and chemistry, researchers said.
Jack Britton, an associate director at IFS, said: “The results also starkly highlight the ongoing challenge in recruiting teachers into high-priority subjects, as returns to PGCE qualifications for maths and science graduates are very low.”