This study investigated the extent to which racialisation shapes EFL learners' conceptualizations of the 'native speaker' construct through an experimental design. Three hundred and fourteen university students studying at English-medium universities in Turkey were invited to take an online matched guise test. They were assigned to either the control group or the experimental group randomly. The participants in the control group were presented with photos of women in their late 20s, accompanied by 30-second speech samples recorded by White, Midwestern American women. In the experimental group, the same speech samples were accompanied by photos of similarly-aged women from racially minoritized backgrounds. The participants responded to 14 statements about each speaker on a five-point Likert scale. The statements were created based on the various qualities commonly referred to in the literature when defining 'native English speakers.' They referred to both linguistic factors such as fluency, intelligibility, age of language acquisition, intuitions about grammar, etc., and non-linguistic factors such as citizenship of an Anglophone country, birthplace, etc. The results revealed that the participants rated the speakers in the control group (White speakers) as significantly more 'native' than some speakers of colour. The discussion includes implications for teacher education and employment.