Communication skills are fundamental in healthcare, but assessing them among medical students presents challenges. In the Indian context, the lack of a specific assessment tool further compounds the issue. Thus this study aimed to develop and validate an observation-based communication skills checklist tailored to Phase I Bachelor of Medicine and Bachelor of Surgery (MBBS) students. The checklist was developed using both inductive and deductive approaches and underwent rigorous testing to ensure its reliability and validity. After piloting, the finalized version was administered to 84 Phase I MBBS students. Results indicated a critical content validity ratio of 0.78, face validity of 0.80, and an impressive Cronbach's alpha of 0.91, indicating good internal consistency and reliability of the checklist. The students scored over 80% in all checklist domains, except for empathy (73%) and support (74%), highlighting areas for potential improvement. Nonetheless, about 75% of students expressed satisfaction with the checklist's communication skills assessment. The feedback from faculty members was positive, as they found the checklist was easy to use, quick, and effective for evaluating communication skills. Consequently, the checklist's introduction has been well received by both students and faculty. In conclusion, the developed checklist proves to be an effective and valid instrument for assessing communication skills in Phase I MBBS students. By integrating this tool into observed station clinical examinations, medical educators can comprehensively evaluate students' communication behaviors. Moreover, the checklist serves as a valuable resource for bridging the gap between theoretical knowledge and practical application, enabling future physicians to excel in doctor-patient interactions, a crucial aspect of patient-centered care.NEW & NOTEWORTHY This article presents a highly unique and novel approach by introducing a structured checklist for communication skill assessment in medical students. Its rigorous validation process ensures reliability and effectiveness, while its adaptation to sociocultural norms highlights its relevance and applicability. The user-friendly design with a single-page layout and dichotomous scale further enhances its practicality in objective structured clinical examinations. The developed checklist equips educators with a valuable resource to assess and improve students' communication abilities.