It is uncomfortable but well documented: the way a person sounds affects how they are judged, independently of what they say. For leaders who present, pitch and negotiate in English as a second language, the research is worth understanding clearly — both what it shows and what it does not.
What the studies show
In a controlled study of sales presentations published in the Journal of Personal Selling & Sales Management, Tsalikis and colleagues (1991) found that a standard American accent drew more favorable ratings than a foreign accent on every dimension they measured, including credibility and intention to buy.
Lev-Ari and Keysar (2010), writing in the Journal of Experimental Social Psychology, asked listeners to rate the truthfulness of trivia statements read aloud. The same statements were rated less likely to be true when spoken with a non-native accent, even when listeners were told the speakers were simply reading statements written by someone else. The authors attributed the effect to processing difficulty: speech that was harder to process made the content itself seem less credible.
A 2024 meta-analysis in Personality and Social Psychology Bulletin by Spence and colleagues pooled 139 studies with 4,576 participants. Speakers with standard accents were rated significantly more hireable, and the gap was largest in roles with heavy communication demands, such as sales.
What the studies do not show
It would be easy to read this research as saying that any accent is a liability. That is not what it shows. Much of the effect runs through ease of understanding rather than accent as such. In widely cited work on second-language speech, Munro and Derwing (1995) showed that how strong an accent sounds, how easy it is to understand and whether it is actually understood are related but distinct. Many speakers with a clearly noticeable accent are highly intelligible and easy to follow.
That distinction matters for anyone deciding what to work on. The goal worth pursuing is not the elimination of an accent. It is removing the specific features that make listeners work harder.
The research does not ask you to sound like someone else. It suggests that the effort your listeners spend is the variable worth managing.
What is within your control
Listener effort is driven by a relatively small number of speech patterns: word stress, emphasis within a sentence, certain vowel and consonant contrasts, and pacing. These can be learned at any stage of a career, and for fluent speakers they respond well to targeted, well-structured practice.
Context matters just as much. The biases documented in these studies operate most strongly when listeners form quick judgments with limited information: a first meeting, a short pitch, a recorded call. These are exactly the moments where preparation on your real material pays off most.
A measured conclusion
The evidence supports two conclusions at once. Accent-based bias is real, and organizations should take it seriously. And individual leaders are not powerless in the meantime: by reducing listener effort in the moments that matter, they can make sure their expertise is what the room remembers.
Sources
- Tsalikis, J., DeShields, O. W., & LaTour, M. S. (1991). The role of accent on the credibility and effectiveness of the salesperson. Journal of Personal Selling & Sales Management, 11(1), 31–41.
- Lev-Ari, S., & Keysar, B. (2010). Why don’t we believe non-native speakers? The influence of accent on credibility. Journal of Experimental Social Psychology, 46(6), 1093–1096.
- Munro, M. J., & Derwing, T. M. (1995). Foreign accent, comprehensibility, and intelligibility in the speech of second language learners. Language Learning, 45(1), 73–97.
- Spence, J. L., Hornsey, M. J., Stephenson, E. M., & Imuta, K. (2024). Is your accent right for the job? A meta-analysis on accent bias in hiring decisions. Personality and Social Psychology Bulletin, 50(3), 371–386.