Abstract: The study was carried out within the older Kiambu District in three banks; Equity Kenya Commercial Bank and Cooperative Bank. The research primary focus was to attest the effect of agency banking satisfaction in relation to customers’ growth in the banking sector. This is because Commercial banks have pioneered in ascertaining colossal agents despite the short period after the instigation of the program by Central bank. Descriptive research design was adhesively used to hold together critical research variables. It afforded researcher with a pathway that aided in spawning a well-defined structure. The researcher beheld research design as the engine that drove his entire research to its packed completion [1]. The descriptive design selected provided genuine means in achieving the itemized research objectives through empirical evidence that was acquired economically. Both non-probability and probability sampling techniques were used. Purposive sampling was used in selecting the three banks of study out of the eight banks practicing the agency banking, the scope area of study and the sample size drawn to represent the customers and the bank employees. Stratified randomly technique was used to survey two customers from each of the 28 agents sampled. The findings of the study shows that 54 out of 56 customers responded giving a 96.33% Response rate. Descriptive research design was used to analyze information statistically. From the findings, an average of 600,000 customers transact on agency banks daily. This stimulates an opening of decongesting the banking halls. The study also found that 80.3% of these customers are satisfied by services rendered by branchless banking.