In the process of development and modernisation or updating lands or buildings register database the knowledge of the accuracy of analytical determination of areas is required. The knowledge of accurately determined areas is also indispensable for other activities, as e.g. in the case of geodetic maintenance of investments or in the process of control of direct subsidies for agriculture, which are performed within the Integrated Administration and Control System (IACS). In the case of double determination of area of an object, basing on co-ordinates of its vertices, determined from two independent measurements of the same accuracy, the results of calculations differ from one another. The value of that difference, generated in the natural way - following the law of error propagation - should be discussed with respect to its permissibility. This paper presents the analysis of technical and legal regulations, which are obligatory in Poland and which concern permissible errors of analytical determination of areas. Then, a method of determination of values of permissible differences of double determination of areas of cadastral (and other) objects basing on co-ordinates of vertices, under the assumption that those areas are determined with obligatory accuracy (i.e. which total error of position of a point does not exceed O. I O m) and with consideration of shapes of a geometrical object and its area is presented. A formula, which defines the maximum value of the permissible difference of double calculation of an area, which is the function of the parcel area, its shape and the accuracy of determination of position of vertices, has been proposed. Results obtained with the use of the proposed formula were then compared with those obtained with the use of the formula, which recently is obligatory in Poland, as well as other formulae acquired from professional literature. It has been proved that in order to record areas of cadastral objects according to existing regulations, the accuracy of determination of position of border points, should be considerably improved.