Objective This study aimed to validate the Cultural Humility and Enactment Scale (CHES) through (a) examining its factor structure with multiple samples; (b) employing item response theory (IRT) analysis to examine its item-level characteristics; (c) reducing potential redundancies among items; and (d) conducting measurement invariance (MI) testing. Method The sample included a total of 610 individuals with diverse demographic backgrounds recruited from Mturk. Analyses included exploratory factor analysis (EFA), IRT analysis, confirmatory factor analysis (CFA), and multi-group CFA. Results We replicated the three-factor structure and retained the 21-item CHES (CHES-21), which showed equivalent information coverage and superior model fit compared to the original 29-item version. We also obtained evidence for MI of the CHES-21 between White and nonwhite clients and between male and non-male clients. Conclusion Evidencing reliability and validity with a sample of adult clients, the CHES-21 can be effectively incorporated into counseling practice and counselor training.