Today, in 2015, the Millennial generation accounts for approximately 1,224,376,230 people (U.S. Census Bureau, 2006) and embraces all individuals between the age of thirteen and thirty- three years old (i.e. teenagers, college students, young adults and professionals). This figures mean that the youth travelers will soon become not only the next generation of managers in the industry, but also the largest tourist group to be served. Thought, in the recent years, the attention of scholars and professionals has been highly oriented towards this age group, there is a lack of research, which goes beyond the national boundaries and explores possible cross- cultural differences among the members of this cohort. This thesis compares the travel motivation and the activity preferences of the Millennials from two countries- the United States and the United Kingdome. The comparison is based on respondents’ nationality, gender, marital status, income, education, age group, and the children factor. It seeks to identify existing differences and similarities among the participants and by doing so to contribute to the market knowledge in terms of Millennials needs and preferences. The findings of this study revealed, that the American and the English Millennials proved to be quite homogeneous when it comes to travel motivation and destination activity preferences. The most important motivational factors for both were relax, the need to escape from the ordinary, and the desire to experience different lifestyle. Similarly, both nationalities agreed that the most attractive destination activities were to try local food and to go sightseeing. Though there were plenty of similarities, the present study discovers also many differences, regarding motivation and activity preferences, between the nationalities, the genders, and the respondents with different backgrounds (e.g. education, income, marital status, etc.).