Members of Cluster Sofia City of Knowledge can be commercial companies, scientific organizations and its subdivisions, training organizations, incl. Universities and schools, technology centers and scientific unions, non-governmental organizations, employers' organizations, public organizations and foreign legal entities working in knowledge intensive sectors, primarily ICT and creative and recreational industries, and who are interested in pooling efforts to build A strong local knowledge economy.

Cluster members are those companies and organizations that see their place in the value and supply chains in the technology areas in which they work and collaborate with other actors in these chains at the regional level to seek better and more profitable access to new technologies, New markets, shared development infrastructure, information and know-how.

Cluster members understand and support the Sofia City of Knowledge concept and wish and can help to achieve the mission and goals set out in this concept, seeing it as an opportunity to create a better environment for development.

Each member of the cluster imports an annual membership fee, the amount of which is determined by a decision of the General Assembly at the beginning of each calendar year. All members of the cluster are equal in terms of both their participation in the cluster's activity and management and the amount of membership fees, which is one of the sources of funding for the association.

For the year 2019 the amount of the annual membership fee of the members is determined by a decision of the General Assembly of 10.06.2019 and is available here.