The V4 countries (Poland, Slovakia, Czechia, Hungary) hold significant importance within the European Union, contributing nearly 20% of the EU’s arable land and 10% of its crop output from 2018 to 2020. The study focuses on companies as organizational entities engaged in arable crop production, representing a specific segment of agricultural producers. The objective is to analyze the concentration and financial performance of these companies in the V4 countries during the period 2018–2020. Financial data from 822 companies in Hungary, 226 in Slovakia, 17 in Czechia, and 967 in Poland were processed from the EMIS database (Emerging Market Information System). In Poland and Czechia, a significant proportion of the companies were classified as micro-enterprises, while in Hungary and Slovakia, they were predominantly small farms. The Gini index indicates a high concentration of Polish farms, a medium concentration of Hungarian and Slovakian farms, and a low concentration of Czech companies. In terms of financial profitability, Hungarian and Polish companies are the most favorable, while Slovak farms are the least favorable. Polish companies exhibit significant heterogeneity, which may also be attributed to high concentration. The results suggest that higher financial profitability is associated with a lower debt rate in the capital structure. Based on the examined sample, there is no close relationship between farm size and financial efficiency in the case of companies engaged in arable crop production in the V4 countries. This study also found that as farm size increases, the profit (EBIT) tends to increase, but the magnitude of this effect varies among the companies in different countries. The study’s findings also support that other factors play a role in the development of profitability.