This paper is dedicated, both theoretically and conceptually, to a methodical approach towards the efficiency evaluation of proposed smart city solutions. The implementation of smart solutions in proposed projects and activities is supported by a complex assessment of benefits and costs as part of a cost benefit analysis (CBA) with the goal of maximizing the efficiency of such a solution, especially in the case of public activities for which it is typical to lack a market evaluation. A smart solution can be defined as an innovative and functional approach towards solving situations in a responsible way and with positive consequences for society. These smart solutions represent the core of the smart city concept, which together with the smart region concept presents a new economic domain where new markets or market segments offering innovative and intelligent (tangible and intangible) solutions for said cities and regions can be developed. CBA and feasibility analyses represent suitable tools for evaluation of socially and economically acceptable projects and their implementation in real life. The efficiency of these solutions is then proved by benefit and cost comparisons under the condition that these outcomes are acceptable for all stakeholders. Methodically, the paper is structured inductively. The detailed literature review provides the basis for a formulation of general principles of using a CBA for innovative smart city solution efficiency evaluations based on chosen cases, for example, from the Moravia Silesian region. Due to the originality of each submitted project, it is possible to use this proposed methodical approach of CBA applications as a primary analytical frame and it is necessary to add the specific attributes of each solution that is being evaluated.