Over the years, we can observe that farmers take up other gainful activities directly related to the agricultural holding (OGA), which affects their economic results. The aim of the study is to show the importance and specificity of OGA in the case of Polish farms. OGA are presented on the basis of data from individual farms of the Polish Farm Accountancy Data Network (FADN) dated 2019 (1086 holdings). The analysis groups farms by types of farming, economic size classes, and FADN regions. The majority of farms with OGA are farms with agricultural production as core activity. Most of the farms with OGA are small in terms of area and economic class, and specialized in field crops. The output from OGA in the examined group of farms amounted to an average of PLN 12,295 per farm. The most common type of OGA is services using farm equipment and processing of agricultural products. The research results presented in the paper indicate that OGA is a phenomenon that may gain in importance and significantly affect farmers’ income.