The Body Image Acceptance and Action Questionnaire (BI-AAQ), a measure designed to assess body image flexibility, was originally developed for and psychometrically investigated with nonclinical populations, but it has been recently administered to people with binge-eating disorder (BED) symptomatology. Tests of measurement invariance are needed to understand whether the BI-AAQ operates in the same way for BED and non-BED populations, thereby ensuring meaningful comparison across these groups. We thus tested the measurement invariance of the BI-AAQ in participants with and without clinically significant BED symptomatology. Data were analyzed from 358 community-based participants. Participants were either classified as with (n = 179) or without (n = 179) "probable BED" based on self-reported symptom frequency. An unacceptable model fit was found across both groups, indicating that the unidimensional structure of the BI-AAQ was not replicated. We then sought to confirm the unidimensional structure of a recently proposed five-item version of the BI-AAQ. A unidimensional structure of this abbreviated version was replicated, and tests of measurement variance were upheld. Internal consistency, convergent validity, and incremental validity were documented for both the original and abbreviated BI-AAQ across individuals with and without BED symptomatology. Present findings provide further psychometric support for an abbreviated five-item BI-AAQ, although it is important for future research to replicate both the full and abbreviated BI-AAQ in more diverse samples. Overall, an abbreviated BI-AAQ may be an attractive alternative for researchers studying body image flexibility. (PsycINFO Database Record (c) 2019 APA, all rights reserved).