The research, carried out by Dr Nick Drydakis of Anglia Ruskin University and published by SAGE in the journal Human Relations, involved 144 young people -- all first-time job seekers -- making 11,098 applications. The study, the first of its kind ever conducted in the UK, found that gay applicants of both sexes are 5% less likely to be offered a job interview than heterosexual applicants with comparable skills and experience.
The firms who offer interviews to gay male candidates pay an average salary of 2.0% less than those who invite heterosexuals for interview (£23,072 compared to £23,544). For lesbian women the average salary is 1.4% less (£22,569 compared to £22,907).
Gay men receive the fewest invitations for interviews in traditionally male-dominated occupations (accounting, banking, finance and management jobs), whereas lesbians receive the fewest invitations for interviews in traditionally female-dominated occupations (social care, social services and charity jobs).
In the accounting, banking, finance and management sector, the study found 74 occasions when only the heterosexual candidate was offered an interview and not the gay male candidate with comparable skills and experience, but no instances of only the gay male candidate being offered an interview.
Similarly, there were 63 examples when only heterosexual women were offered an interview in the social care, social services and charity sector, but no examples of only the lesbian candidate being offered an interview.
The study was carried out with the help of 12 students' unions at universities across Great Britain and Northern Ireland.
Of the 2,312 students who volunteered for the study, Dr Drydakis was able to match 72 students whose CVs mentioned having a prominent role in their university's LGBT (lesbian, gay, bisexual and transgender) society with 72 students whose skills and experiences were identical, but whose CV didn't indicate their sexuality.
The participants were all third-year undergraduates, 21 years old, British nationals and unmarried. They were all predicted to achieve an upper second class degree (2:1).
In pairs, the 144 students applied for 5,549 jobs (11,098 separate applications) that had been advertised on 15 of the UK's leading recruitment websites over a two-month period.
Dr Drydakis, Reader in Economics at Anglia Ruskin University, said: "Because of the limited research carried out so far into the experiences of gays and lesbians in the labour market, the disadvantages and discrimination they experience has gone unnoticed and therefore unchallenged.
"Despite measures to encourage openness and discourage discrimination, including the introduction of the Equality Act of 2010, it is evident from my research that gays and lesbians are encountering serious misconceptions and barriers in the job market.
"It is also clear that people who face biased treatment in the hiring process must spend more time and resources finding jobs, and firms lose potential talent as a result of biased hiring."