In India, strategic marketing strategy for customer retention is more effective when it incorporates Electronic Customer Relationship Management (E-CRM). Businesses can collect and analyze enormous volumes of client data using E-CRM systems, giving them deep insights into the preferences, actions, and buying patterns of their customers. Customer satisfaction and loyalty are raised by the more individualized and focused marketing techniques made possible by this data-driven approach. In the Indian context, E-CRM assists companies in catering to the distinct requirements of different client segments in an extremely competitive and diverse market. Stronger relationships are fostered via E-CRM, which guarantees timely and consistent customer involvement by automating customer interactions and optimising communication channels. By cultivating a devoted clientele, this all-encompassing strategy fosters long-term growth in addition to improving customer retention. E-CRM is therefore essential for strategic marketing strategy targeted at retaining customers in the ever-changing Indian market. A sample of 231 respondents was collected from people in business and marketing sector. The factor that identifies the role of E-CRM in effectiveness of Strategic Marketing Planning for customer Retention are Loyalty Programs and Rewards, Customer Feedback and Engagement, Enhanced Customer Service, and Data-Driven Decision Making.