Researchers from Anglia Ruskin University (ARU) analysed 24 studies published between 2012 and 2020 covering countries in Europe, North America and Australia.
Their analysis, published in the Journal of Population Economics, indicated that gay men earned on average 6.8 per cent less than heterosexual men across all countries covered in the study.
Bisexual men earned 10.3 per cent less than heterosexual men on average, while bisexual women earned 5.1 per cent less than heterosexual women.
Lesbian women earned 7.1 per cent more than heterosexual women, with researchers suggesting “masculine characteristics” as one possible explanation for this.
In the UK, gay and bisexual men together earned 4.7 per cent less than heterosexual men, while in the United States they earned 10.9 per cent less.
In the UK, workplace prejudice against individuals due to their sexual orientation or sex is prohibited under the Equality Act of 2010.
Professor Nick Drydakis, author of the study and director of the Centre for Pluralist Economics at ARU, said: “The persistence of earnings penalties for gay men and bisexual men and women in the face of anti-discrimination policies represents a cause for concern.
“Legislation and workplace guidelines should guarantee that people receive the same pay, and not experience any form of workplace bias simply because of their sexual orientation or gender identity status.
“Inclusive policies should embrace diversity by encouraging under-represented groups to apply for jobs or promotions and providing support to LGBTIQ+ employees to raise concerns and receive fair treatment.
“Standing against discrimination and celebrating and supporting LGBTIQ+ diversity should form a part of HR policies.”
Suggesting an explanation for why lesbian women earned more than heterosexual women, according to the research, Prof Drydakis said: “Arguments focusing on lesbian women’s earnings premiums in relation to masculine characteristics, which stereotypically characterise lesbian women and demonstrate leadership, have been utilised to evaluate their experiences.”
He said that a “peripheral explanation for the lesbian earnings premium may revolve around women with children earning less than women without children”.
“Lesbian women might prove less likely to have children than married women, so it makes sense that they may earn more because of their commitment to the labour market,” he said.