A More in Common survey of over 3,300 adults across England, Scotland and Wales found that accent-related anxiety or 'accent bias' is still an issue in British workplaces.
Areas or accents that reported the most concern were those from Newcastle ('Geordies'), East London ('Cockneys') and Wales, with people with strong Birmingham accents the most likely to feel that their accent had cost them a promotion.
Those from the West Country reported the highest rate of having their accent mocked or criticised by colleagues.
13% of those polled admitted to changing the way they speak in order to sound more professional, with Cockneys and people from Scotland the most likely to attempt to soften their accents.
Accents from Liverpool (15%) and Birmingham (11%) were perceived as facing the higest levels of bias nationally.
Lara Newman is the founder of Common Ground, the commissioners of the survey, and said: “It’s hard enough trying to get jobs or promotions in professions that for decades have recruited from only certain classes or backgrounds and appear to exclude those with regional accents.
“This new polling really underlines the deep-seated problems within recruitment and career development. In my industry – real estate and commercial property – I believe that people in charge of creating places and communities, including major public building projects, schools, hospitals, and social housing, should reflect the communities they serve.
She added: "Diversity must mean more than just replacing one gender for another, or ‘token’ hires; it’s about opening up routes to successful careers for people who have, until now, been ignored, excluded or discriminated against, either because they are from the ‘wrong’ class, been in care, disabled, LGBTQ+ or neurodiverse.
“Challenging deep-rooted, outdated attitudes, including bias against accents, will lead to industry-leading inclusion and benefit society as a whole.”
It's the stance of most employers that they aim to treat applicants and employees equally, regardless of accent. Speaking to the BBC, LinkedIn career expert Charlotte Davies says that the "direction of travel is encouraging", though there is still progress to be made.
She said: "Hiring is increasingly about skills, not background or polish. Your accent is part of your story, and the workplaces getting this right, treat that as a strength, not something to smooth out."