Poland’s rural areas are characterised by a significant degree of development diversity, especially in the case of communes—the smallest territorial units. For development to take place, the entity responsible for its creation must incur the necessary investment expenditures. By implementing the public tasks assigned to them, communes are responsible for ensuring sustainable local development, which indirectly affects regional development and shapes the development of the entire country. Therefore, this article aims to assess the level and diversity of rural commune investment activities and their impact on the development of Poland’s rural areas. The empirical research conducted was aimed at verifying the following hypothesis: “The highest investment activity can be observed primarily in rural communes located in Eastern Poland”. The Regions of Eastern Poland are characterised by their peripheral location, both in the country and all of the EU. The research covered the 2007−2018 period due to a particular increase in local investment projects thanks to such factors as obtaining EU funding, as well as others. The research included one- and multidimensional analyses of the phenomenon examined with the use of the TOPSIS method to obtain the value of the synthetic measure of the rural commune investment activity level. The designated investment activity classes were the basis for the analysis of their links with their location within the macroregion, as well as their socio-economic status. The research has shown that the most pro-investment municipalities are located primarily in the Southern and Eastern Macroregions while those spending the least on investment projects are situated in the North-Western and Northern Macroregions. Thus, the research hypothesis put forth in the article has been confirmed. This delimitation is due to additional state resources being provided to the less developed eastern areas of Poland. Citizens living in these regions can not only take advantage of the funding provided as part of the Regional Operational Programmes, but also the Eastern Poland Programme dedicated to helping them.