The paper describes the predicted effects for communal budgets of the introduction of an income tax for farms which would replace the present agricultural tax. Research conducted in the farms located in the Wielkopolska, Slask, Mazowsze and Podlasie regions, which participated in the FADN system, has indicated that the imposition of an income tax meant as the source of incomes of communes would be very beneficial for their budgets. The advantages would be far greater in the Mazowsze and Podlasie regions. If it is accepted that communal budgets will have the same share in the income tax paid by farms as in the income tax paid by natural persons (39.34%) then, on the whole, this solution would not be beneficial for them. This situation generally relates to the Wielkopolska and Slask regions because in the latter region the inflow of means from communal budgets was higher than the inflow of cash from the agricultural tax. Their earning power situation would be even more unfavourable if it was accepted that the proposed income tax should be equal to the corporate income tax (6.71%). The introduction of an income tax for farms would be advantageous to the state budget. In individual communes the advantages (or their absence) of the introduction of the income tax depend on the number of operating farms, their acreage, type of farming and the adopted rules of the communes' participation in incomes from this tax. For the farms that are not engaged in the production of goods for the market the introduction of a flat tax would be more suitable.