A method for operating an elevator system in a building, wherein the elevator system comprises a destination call control device and an elevator car, which can travel between floors (L1, L2, L3) of the building and has a defined passenger capacity, with said method comprising the steps of: evaluating a first destination call being input on a floor (L1, L2, L3) by a first passenger at a first point in time in order to determine first call information from the first destination call, wherein the first call information contains data on a call input floor (L1, L2, L3) and/or a destination floor (L1, L2, L3); using the first call information for determining if a number of additional passengers are to be assigned to the first destination call, wherein the number of additional passengers results in an additional space requirement in an elevator car handling the first destination call, and wherein said determination comprises - accessing a database, in which a plurality of datasets can be stored, wherein a dataset has predefined data fields that describe a call situation, and wherein a first data field indicates the call input floor, a second data field indicates a time window, a third data field indicates the destination floor and a fourth data field indicates the number of additional passengers for the call situation described in the dataset, and - determining if the first destination call corresponds to a call situation stored in the database; generating information on the additional space requirement if a number of additional passengers are to be assigned to the first destination call; and, if a number of additional passengers are to be assigned to the first destination call, allocating the first destination call with the aid of an allocation algorithm by using information on the additional space requirement in order to transport the first passenger from the call input floor (L1, L2, L3) to the destination floor (L1, L2, L3), wherein the information on the additional space requirement is kept separate of the first destination call and both are fed to the allocation algorithm separately in order to allocate the first destination call. evaluating a first destination call being input on a floor (L1, L2, L3) by a first passenger at a first point in time in order to determine first call information from the first destination call, wherein the first call information contains data on a call input floor (L1, L2, L3) and/or a destination floor (L1, L2, L3); using the first call information for determining if a number of additional passengers are to be assigned to the first destination call, wherein the number of additional passengers results in an additional space requirement in an elevator car handling the first destination call, and wherein said determination comprises - accessing a database, in which a plurality of datasets can be stored, wherein a dataset has predefined data fields that describe a call situation, and wherein a first data field indicates the call input floor, a second data field indicates a time window, a third data field indicates the destination floor and a fourth data field indicates the number of additional passengers for the call situation described in the dataset, and - determining if the first destination call corresponds to a call situation stored in the database; - accessing a database, in which a plurality of datasets can be stored, wherein a dataset has predefined data fields that describe a call situation, and wherein a first data field indicates the call input floor, a second data field indicates a time window, a third data field indicates the destination floor and a fourth data field indicates the number of additional passengers for the call situation described in the dataset, and - determining if the first destination call corresponds to a call situation stored in the database; generating information on the additional space requirement if a number of additional passengers are to be assigned to the first destination call; and, if a number of additional passengers are to be assigned to the first destination call, allocating the first destination call with the aid of an allocation algorithm by using information on the additional space requirement in order to transport the first passenger from the call input floor (L1, L2, L3) to the destination floor (L1, L2, L3), wherein the information on the additional space requirement is kept separate of the first destination call and both are fed to the allocation algorithm separately in order to allocate the first destination call.