Background: Internal communication is that channel used to create, process and convey information within an organization.The purpose of this study was to examine the effect of internal communication on employee productivity in HEIs in Ghana. In particular, the study investigates the factors that affect the productivity of academic and non-academic workers in the educational institutions in Ghana, namely, vertical communication, horizontal communication and digital communication channels. Design/Methodology/Approach: Quantitative explanatory research design was used. The sampling method for data collection was the stratified random sampling technique, where a sample of 412 number of participants was selected from five public universities in the Ghanaians. The descriptive statistics and correlation Pearson and multiple regression analysis were used to analyze the data while being assisted by IBM SPSS version 26 software. The mediation analysis used Hayes' PROCESS Macro (Model 4). Results: The findings found that all three vertical, horizontal and digital elements of internal communications have a large positive effect on employee productivity. The strongest predictor was via the digital communication channels and the second strongest predictor was from horizontal communication with peers. The results indicated that internal communication had a partial mediation effect on organizational trust and employee productivity, which illustrated that organizational trust, was a psychological medium in strengthening employee productivity from internal communication. Research limitations/implications: The study is cross sectional in design and limited to the five public universities in Ghana making it hard to make a cause-effect statement and generalizing the findings to a broader sample for which there are other studies. Longitudinal study designs should be adopted, and the studies should be extended to cover other sub-Saharan countries, such as private HEIs. Practical impacts: University administration and HR practitioners need to put emphasis on communication system integration, open information sharing and digital communication facilities. Insonia Ways of Communication (OWC) is important to improve staff productivity and institutional performance as it ensures open timelines, and rich feedback loop. Originality/value: This study fills gaps in the literature related to HEI management and organizational communication through empirical findings in a Sub-Saharan African university setting, and through the finding of the mediated effect of organizational trust in the internal communication-productivity relationship, which has not received much attention in the higher education literature to date.