Globally, nearly one in five workers say they’ve been passed over for business trips — not because of costs or lack of seniority, but because of the way they speak. 

In a survey of 3,850 business travelers in 25 markets, 18% of men and 16% of women said they felt they lacked equal opportunities for business trips because of their accents, according to a report published in June by SAP Concur.

The results were most pronounced in Asia-Pacific, with the highest percentage of people saying their accents had affected their work travel coming from Australia/New Zealand (31%), Taiwan (26%) and Singapore/Malaysia (25%).

Overall, the survey showed more people felt their accents played a bigger role in their work travel opportunities than their physical appearance, ethnicity or sexual orientation.

Shan, a former marketing manager at a global tech company, told CNBC her department chose speakers for events in Asia-Pacific based, partly, on the way they spoke.

“But, of course, we won’t tell them [that] in the face,” she said.

Employees were given “internal ratings” that took their accent into consideration, she said.

Shan, who asked that CNBC not use her real name owing to the sensitivity of the subject matter, said attendees from Australia and New Zealand told the company they couldn’t understand speakers from Southeast Asian countries such as Indonesia and Vietnam.

As a result, her company chose speakers with accents that most of the audience could understand, Shan said.

“Audiences’ attention spans are getting shorter,” she said. “So it’s important for our speakers to be engaging [and] easily understandable.”

The idea that one accent is easier to understand than another is subjective, said Tracey Derwing, adjunct professor educational psychology at the University of Alberta.

“There is no universally ‘easy’ accent,” she said, as a listener’s native language influences their ability to comprehend the speech of others.

“English and Dutch are closely related … native speakers of one of those languages usually will not have too much trouble understanding” one another, said Derwing.

Vietnamese and English, on the other hand, are extremely different, she said. Not many Vietnamese words end in consonants, and none end in consonant clusters, which have two or more consonants together.

“So it is quite hard for a Vietnamese speaker to perceive the sounds at the end of English words because they are starting with a first language that has very few,” Derwing said.   

However, accent problems go well beyond communication, she said.

“Some people react negatively to accents … and employers know that,” Derwing said.

“They may not want to risk sending someone who has an accent despite the fact that the employee is easy to understand and fully capable,” she said. “Some businesses have adjusted their practices to take into account their clients’ negative attitudes.”

It’s not surprising that employees’ accents play a role in determining business travel, said Regina Kim, an assistant professor of management at Fairfield University’s Dolan School of Business.

“Companies would want to send someone that can best represent the firm,” she said. “Based on research, this person wouldn’t be someone with an accent.”

In the United States, a person is considered to have “no accent” if they speak General American English or Broadcast English, which is perceived as being without regional characteristics. Companies such as the New York-based Accent Advisor teach people how to speak with this accent, which the company’s website claims will help speakers “boost professional opportunities” and “overcome cultural biases.”  

Accent bias can be even more pronounced for speakers with non-English mother tongues. Research shows that non-native speakers are often perceived negatively, regardless of their competence levels, Kim said.

“Individuals who have non-native accents are viewed as less intelligent, less loyal, less trustworthy and less competent. They tend to be rated low in status, especially when their accents are perceived as difficult to comprehend,” she said.  

As a result, non-native speakers are less likely to be hired, more likely to be assigned lower status jobs, and earn less, she said.

Leadership specialist and author Ritu Bhasin said there’s an “accent hierarchy” in today’s globalized world.

Accents from Britain, Australia, New Zealand, Canada and the United States are at the top of the hierarchy, she said.

Kim agreed, saying studies show that the Standard British English accent has a “covert prestige,” with speakers being perceived as more trustworthy, intelligent and attractive.

The opposite, however, is true of Asian accents, said Bhasin.

“When you are from Asia, whether that’s East Asia, South Asia, West Asia, in particular, because of racism, people treat you less favorably when you start to speak,” she said.

Ultimately, it’s not just about speech, said Bhasin, “it’s about nationality and ethnicity.”

Elizabeth, who asked that CNBC not use her real name to protect her company’s name, said she’s been ridiculed at work because of her accent.

“There were many incidents where I would have work discussions with a colleague, and she would just shut me down by saying: ‘Your English is so bad. I don’t understand what you’re saying.'”

The 35-year-old worker, who moved to Singapore seven years ago, said she communicates well enough to be understood, and feels something else is at play.

“It’s not my … English. It’s my accent being used as a weapon against me — against where I’m from, or the people who are disliked in this region — such as those from China,” said Elizabeth, who is from Taiwan.

The presence and severity of accent bias in the workplace may depend on industry, location and company culture, said Kim.

“For example, having a French accent in a wine industry may be ‘better’ because there’s an industry-accent fit,” she said.

As for location, workers with French, Italian, Spanish or German accents may be more accepted in Europe, where their accents are more common, Kim said. They may, however, feel more self-conscious working for companies in the United States, she added.

SAP Concur’s global workforce survey supports that, with Europeans being the least likely (13%) to say that their accents had affected their business trip opportunities.  

Accent bias can be worsened by national stereotypes that listeners associate with the way their colleagues talk, said Kim.

“Studies have shown that French accents are commonly appreciated as more favorable than Russian accents,” she said, “which corresponds with attitudes toward the nationalities.”

Elizabeth said she feels she must work “extra hard” for colleagues to respect her. Tired of being disrespected at work, she eventually forked out her own money for a business English course at the British Council Singapore four years ago. 

“I cannot control people and what they think about me. I can only try to improve my communication skills,” she said.

For more on the controversy surrounding “accent reduction classes” and ways that employers can reduce accent discrimination, read the second part of CNBC’s coverage on accent bias in the workplace, to be published soon.   

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