Describes a study performed in Leicestershire, United Kingdom to develop a reliable and valid scale for the measurement of the perceived service quality of bank services. The Cooperative Bank (CB) and Islamic Bank of Britain (IBB) which located in Leicester, UK has been chosen as a sample for the research field study. A sample of retail banking customers in The Cooperative Bank and Islamic Bank of Britain was surveyed through a questionnaire. The proposed scale is called SERVQUAL and comprises 33 items named ‘CARTER'' with six dimensions (Compliance, Assurance, Reliability, Tangible, Empathy and Responsiveness), which customized for suitability of The Cooperative Bank and Islamic Bank of Britain. The data gathered, which were derived from customers of The Cooperative Bank and Islamic Bank of Britain through questionnaire is analyzed by using SPSS to compare, to compare the perception of customers in relation to their feeling about the given issues. The results indicate that compliance issues are very important for IBB customers, while the same cannot be mentioned for the CB customers, who give more importance to empathy and responsiveness.