This study investigated the relationship between internal communication and employee engagement at First Bank PLC in Onitsha, Anambra State, Nigeria. The study was guided by three specific objectives: to examine the relationship between feedback mechanism and employee engagement, to assess the relationship between message clarity and employee engagement, and to evaluate the relationship between communication climate and employee engagement. Anchored on the Communication Satisfaction Theory by Downs and Hazen (1977), the study adopted a descriptive survey research design. The population consisted of 200 staff across various First Bank branches in Onitsha, and a census sampling technique was used to include the entire population. Data were collected through structured questionnaires and analyzed using descriptive statistics and Pearson Product Moment Correlation at a 0.05 level of significance.The findings revealed a significant and positive relationship between feedback mechanism and employee engagement (r = 0.473, p < 0.05), message clarity and employee engagement (r = 0.390, p < 0.05), as well as communication climate and employee engagement (r = 0.401, p < 0.05). These results suggest that internal communication components significantly influence how engaged employees feel in their roles. The study concluded that robust internal communication systems enhance employee morale, motivation, and commitment. It was recommended that First Bank PLC strengthen its feedback systems, promote message clarity, and foster a positive communication climate to drive employee engagement. The study fills a knowledge gap in internal communication and employee engagement research in the Nigerian banking sector, particularly within a geographically and organizationally defined context