The study examined the role of Credit Reference Bureau (CRB) in influencing customer credit access in mitigating default risk among commercial banks in Kenya. The study was based on the theories of Adverse Selection and Hazard. The study used a Causal-Comparative descriptive survey design. The target population of the study consisted of all the 43 licensed commercial banks in Kenya and the three licensed credit reference bureaus in Kenya under the Banking Act. The researcher used a census of all commercial bank headquarters bank managers and the three headquarters credit reference bureau managers. To collect primary data, the researcher used questionnaires. Secondary data were collected from CBK loan books and CBK annual Bank supervisory reports. Data was analysed using SPSS and results presented using graphical systems. The researcher used descriptive statistics, which included the mean, median standard deviation and range to show the default rate. The inferential statistical tests comprised correlation, ANOVA regression and Chi-square analysis to test hypothesis. P -values yielded were less than 0.05, which indicated that the role played by Credit Revenue Bureau in influencing customer access to credit and mitigation of Credit Default Rate was significant among commercial banks in Kenya