During the last decades religion has faced significant changes and the number of new religions increased in post-communist countries of Eastern and Central Europe. In Serbia, these changes led to new legal frameworks for both traditional churches and new religious communities. Although neo-Protestant communities were founded in the late 19th and the beginning of 20th centuries, they could be classified as «new religions» since they became more visible after the fall of communism. Neo-Protestants have spread their teachings in ethnically and confessional heterogeneous environments, such as the northern Serbian province of Vojvodina, and especially among ethnic minorities. Unlike mostly homogenous traditional communities in Serbia, neo-Protestants emphasize the principle of trans-ethnicity and trans-nationalism. This paper shows the dynamics of neo-Protestant communities in the region as well as changes that occurred in religious identities of the converts. The paper also indicates how religious transformations lead to diversification within a community that seems mono-ethnic and mono-confessional.