The given article deals with the problem that has received a recent wide discussion in connection with the system of calculating time reform — time zones reduction, the abolition of season time transition, and its forthcoming prolongation, scheduled for autumn 2014. The author estimates the geographical assessment of the Western Siberia regions’ positions in the international time zone map belonging to the 4th time zone (Moscow time plus 3 hours) in accordance with the Russian legislation. Using geographic information systems there have been constructed the maps allowing to visually evaluate advancing local civil time in the respective regions over the standard time or mean solar time and apparent solar time, given the phenomenon of the equation of time. The article displays the inadmissibility in the use of existing calculating time system in the Omsk Oblast in terms of constant throughout the year time since the start of the studying day in full-time institutions and organizations over the 4th time zone. The calculating time problem for the Altai Krai has been discussed in detail. The historical chronology of the time change for the region has been presented. The article justifies the necessity of the geographical assessment for the calculating time reform. From a sociological point of view there have been given a recommendation to solve the calculation time problem by reducing working hours and transferring to the different beginning time of the work (studying day) for different seasons and different areas of the time zones — the time associated with the standard time of sunrise in every district in each season of the year.