The relationship between employee promotion and employee satisfaction in commercial banks has been a controversial issue. Commercial banks in Kenya play an increasingly important role in economic and social development and hence any element of employee empowerment should be strategically done for enhanced benefits to its clientele. However, research reveals that staff satisfaction in Kenya commercial bank is at 37%. This shows that employee work motivation is still low despite existence of this extrinsic reward programme. The main purpose of this study was to investigate how employee promotion affects employee satisfaction among Kenya Commercial Banks Branches in Bungoma County, Kenya. The study adopted a descriptive survey research design to establish the relationship between extrinsic rewards and employee satisfaction in KCB bank Bungoma Branches. The study targeted a total of 185 staff from the three branches of KCB Bungoma branches. Random, proportionate sampling techniques were used to select and apportion 126 respondents from the 185 targeted population. The questionnaires were used as data collection instruments. Content validity was evaluated through the opinion of scholars and experts in strategy implementation as well as through a pilot test which was carried out in a different county to check the reliability of the research instruments. Reliability of the questionnaire was evaluated using the Cronbach alpha test, which provided an acceptable threshold. Data analysis and interpretation was based on descriptive statistics as well as inferential statistics mainly multi-linear regressions and factor analysis using SPSS version 22. Analyzed data was presented suing APA tables. The relationship between employee promotion and employee satisfaction was analyzed. As indicated in the results, the study showed that there was a linear positive and statistically significant relationship between employee promotion and employee satisfaction. The relationship was found to be positive and significant. This implied that employee promotion though present in KCB bank, its effect on employee satisfaction is positive and significant. The study recommends that the Central Bank of Kenya should develop legislation on staff promotion for all commercial banks in Kenya. Banks should endeavour to prioritize motivation for their staff to ensure employee satisfaction. Finally bank staff ought to work with diligence and utmost commitment as a show of gratitude for the banks efforts in motivating them.