As companies increasingly shift from product-oriented to service-oriented business models, long-term customer relationships and recurring service revenues are becoming increasingly important for sustainable growth. This bachelor thesis examines how an established service company can strengthen portfolio growth by improving customer retention.

A mixed-methods approach was applied, combining the analysis of internal business and customer satisfaction data with interviews involving customers and company experts. This enabled the topic to be examined from both a quantitative and qualitative perspective and provided insights into customer expectations, satisfaction drivers, and reasons for switching providers.

The findings show that customer retention depends on more than the quality of the core service. While reliability, technical competence, and responsiveness remain important, customers also place strong emphasis on proactive communication, transparency, personal relationships, trustworthy advice, and continuous value creation. The results therefore highlight the importance of considering the entire customer relationship rather than focusing solely on operational performance.Based on these findings, the thesis identifies opportunities to strengthen customer retention through more proactive and transparent communication, stronger relationship management, enhanced customer value creation, improved internal collaboration, systematic customer feedback, and better use of available data.Overall, the study concludes that combining technical excellence with a consistently customer-oriented service approach and continuous value creation can strengthen customer loyalty, reduce customer losses, and support sustainable maintenance portfolio growth.