This research aims to measure the service quality of e-banking through e-customer satisfaction & e-customer loyalty in the Islamic e-banking sector of Pakistan. For this purpose, we modified the multiple-item scale (E-S-QUAL) model with two new dimensions: availability of online system and personal needs of customers. Additionally, we added two mediators, for instance, religiosity and trust in the Islamic e-banking perspective. We have collected 674 responses from the consumers of the Islamic banking sector of Pakistan through a structured questionnaire. The data were analysed through second-order PLS-SEM (PLS-structural equation modeling) to examine direct and serial mediation. The direct relationship results showed a positive and compelling effect of modified E-S-QUAL dimensions on e-customer satisfaction. Additionally, the e-customer satisfaction has an affirmative and significant association with e-customer loyalty. Moreover, the serial mediation relationship results exhibited that the e-customer satisfaction, trust, and religiosity mediated the modified dimensions of the E-S-QUAL model and e-customer loyalty.