Due to rapid changes in modern technology, economic, cultural and social globalization, as well as other factors, due to the impact, significant changes are taking place in marketing. One of the major trends in modern marketing is an electronic environment and the Internet using for promotion of products and services. To be competitive, businesses need new ways to attract or keep customers, as well as create a loyal, constant and reliable customer base. Thanks to the electronic environment development develops electronic commerce and electronic marketing. Many researches have demonstrated the fact that email marketing provides a faster exchange of information. And successful use of the information the company provides greater business efficiency and profitability. There are many factors that affect the company's various e-marketing activities. Electronic marketing, like classic marketing has external and internal environmental factors that affect the business. Traditionally there are two approaches to treat customer loyalty. Some researchers have investigated the nature of different levels of loyalty; others have explored the influence of individual factors on loyalty. In this article both treatments are combined. The starting point of the paper is to test whether the list of most important factors affecting customer loyalty is dependent on the levels of loyalty of costumers. More specifically the current paper is going to estimate which specific factors in telecommunication sector influence the loyalty rate of the various customers segmented by loyalty. These different approaches allow distinguishing customers as whether behaviorally or emotionally loyal. Behaviorally loyal customers act loyal but have no emotional bond with the brand or the supplier whereas emotionally loyal customers do. Emotional loyalty is much stronger and longer lasting than behavioral loyalty. It’s an enduring desire to maintain a valued relationship. Article aim is: to identify and analyze factors that influence the loyal customer attracting, retaining and using the electronic environment, and e-marketing activities. Research method the author uses well-established quantitative and qualitative research methods: grouping, analysis, statistical method, and so on. Article’s theoretical and methodological background is based on scientific research and publications, publications in mass media and professional literature, statistical information from official sources, as well as authors of studies over the information obtained. Keywords: customer loyalty, loyalty programs, electronic marketing, e-marketing environment, small and medium-sized enterprises.