The eccentric in-plane loading of masonry walls involves complex bending performance that includes second-order effects. In this work, a bidimensional (2D) simplified micro-model for the analysis of this type of failure is developed. An experimental investigation based on 20 tests of full-scale unreinforced masonry walls is performed. The tests are characterised by slenderness and load eccentricity. The analytical methods of Eurocode-6 and ACI-530 are compared with experimental data from the present investigation, other experimental results available in the literature and simulation results from the numerical model.