As part of inter-church cooperation, HEKS/EPER has maintained close ties with the Reformed Church in Hungary (RCH) for decades now. With a 16-per cent share of the population and 1 200 church parishes, it is the country's second largest religious community and an important social institution. The RCH advocates mainly for the Roma population, for people with a disability and for refugees. By nation-wide comparison, the Roma population have a markedly lower level of education, worse job prospects and are more affected by poverty and discrimination. HEKS/EPER supports the RCH in developing projects to educate and help Roma children and adolescents shape their lives. Refugee inclusion entails, among other things, language courses for children and adults, and integrating young people into the school system. The RCH also organizes leisure activities and holidays for differently abled people.
In 2020, HEKS/EPER supported diaconal projects run by about 20 church parishes of the Reformed Church in Hungary. They benefited 1050 disadvantaged Roma children and some 110 refugees. HEKS/EPER also supported church-run social events for 450 young people.