The article presents the economic results and production efficiency for farms specializing in field crops classified by economic size classes. The FADN UE data from 2010 and 2015 were used for the analysis. The income from the farm was a measure of the economic situation. The assessment of production efficiency was carried out at the production and technical level, the profitability of current assets as well as the cost consumption and economic efficiency of production were examined. The debt of farms was also analyzed. Income from the farm without subsidies for operating activities in economic size classes 1-5 successively increased, while for farms in the sixth class there was a strong decline in it, as a result income was a negative value. In 2010, the subsidies covered the loss on production and ensured a certain amount of income, while in 2015 the loss was only partially covered (in 95%). The highest income without subsidies per 1 ha of arable land was obtained on farms from the third and fourth economic size classes (in 2010: EUR 267 and EUR 201, respectively, in 2015 – EUR 161 and EUR 193). Farm production in the third and fourth classes also stand out in terms of production efficiency, while in sixth class of farms, the efficiency was the lowest. Together with the increase in the economic size of farms, their debt increased. In all groups, the liabilities were mostly long-term loans, but its smallest share was found in the sixth class of farms. This means that significant funds were allocated to finance the current operations of these farms.