Introduction. The idea laid down in the Criminal Procedure Code of the Russian Federation on the basis of the Constitution of the Russian Federation, according to which the period of criminal procedural detention should be calculated from the moment of actual restriction of freedom of movement, is not implemented in practice. Since there is a contradiction between the law and its application, it is supposed that the way to solve given problem will be found through the analysis of practice. Methods. The following methods were employed in the work: formal-legal, methods of analysis, induction and generalisation. Results. The current legal regulation, science and practice allow for at least three options to interpret the moment of actual detention and the beginning of calculating the period of the suspect’s detention: the moment of actual capture, the moment of delivery to the investigator (to the body of inquiry) and the moment of drawing up the detention protocol. The last two are the most common in practice, but they do not coincide with the actual intention of the legislator to calculate the period of detention from the moment of actual restriction of freedom. At the same time, linking the beginning of the period of detention to the moment of delivery or the drawing up of the protocol meets the needs of practice due to the objective insufficiency of the 48-hour period, if calculated according to the idea laid down in the law, i.e. from the moment of actual capture. Summarising the results of the analysis of judicial practice, the author concludes that the way to take into account the time of actual restriction of freedom and at the same time not to take away from the investigating authorities the small but very important 48-hour period of detention is to include the time of actual detention in the total period of detention when considering a petition for detention or when considering the case essentially.