AbstractObjectiveThere is debate surrounding how to differentiate between anorexia nervosa (AN) and atypical AN (atypAN) as diagnostic entities, and whether a distinction based on BMI is warranted. Better understanding eating disorder (ED) and emotional symptoms across atypAN and AN subtypes [AN‐restricting (AN‐R), AN‐binge/purge (AN‐BP)], with and without controlling for BMI, can elucidate how atypAN differs from AN subtypes and whether there is a basis for a BMI cut‐off.Methods1810 female patients at an ED treatment centre completed intake surveys. ANCOVAs assessed differences across AN‐R (n = 853), AN‐BP (n = 726), and atypAN (n = 231) groups on ED, depressive, and anxiety symptoms, anxiety sensitivity, experiential avoidance, and mindfulness, with and without controlling for BMI.ResultsRelative to AN‐R, atypAN and AN‐BP groups endorsed significantly higher ED and depressive symptoms, anxiety sensitivity, experiential avoidance, and significantly lower mindfulness (all p < 0.001), but atypAN and AN‐BP groups did not differ from one another. When controlling for BMI, all previously significant differences between atypAN and AN‐R did not remain significant.ConclusionIndividuals with atypAN who have a higher BMI experience more pronounced ED and emotional symptoms, suggesting that relying solely on BMI as a marker of illness severity may be problematic.