The main condition for the structures reliability of buildings and constructions is the meeting the requirements for strength, rigidity and stability of both separate structures and their parts, and the system as a whole. The analysis of stability is of great important for compressed and compressed-bended columns. When analyzing the stability of a separate section of a compressed column located between the beam connections, the correct determination of its effective length is essential. This article is devoted to the issue of determining the effective length in unconventional cases not specified by modern standards. This article is devoted to the issue of determining the effective length in unconventional cases not specified by modern standards. The article describes a general method for determining the effective length of a compressed column of a frame using the instance of an exterior column of the transverse frame of a building. In addition, the influence of the pliability of the beam-to-column connection adjacent to this column on its effective length is considered in the paper. © 2023 Author(s).