In accordance with Clauses 9,20-22 of the Rules for Carriage of Passengers, Luggage and Cargo-Luggage by Public Railway approved by the Resolution of the Council of Ministers of the Republic of Belarus dated 07/17/2015 No. 609: 

In regional business-class, inter-regional trains, international cars or trains of Belarusian Railway (within the Republic of Belarus), a passenger has the right to carry children who are provided with relevant privileges in accordance with legislative acts and international treaties of the Republic of Belarus, at the age of: 

up to 5 years - free of charge without the right to occupy a separate seat with the issuance of free travel documents (tickets) or with the right to occupy a separate seat with payment and issuance of children's travel documents (tickets); 

5 to 10 years - with payment at a reduced tariff and the issuance of children's travel documents (tickets). 

For children over 10 years of age, full travel documents (tickets) are purchased. 

The age of the child is determined on the day of a trip beginning. If the day of a trip beginning coincides with the birthday of a child who is 5 years old, the carriage of the child is carried out under the terms for children under 5 years old. If the day of a trip beginning coincides with the birthday of a child who is 10 years old, the carriage of the child is carried out under the terms for children 5 to 10 years old. 

In regional economy class and city trains, a passenger has the right to carry free of charge children under 7 years old, who are provided with relevant privileges in accordance with legislative acts, with the issuance of children's travel document (ticket). 

Carriage of children under 10 years of age without being accompanied by an adult is not allowed, with the exception of pupils who use rail to study at educational institutions, if there is a certificate that the citizen is a pupil. 

Children traveling on a train without being accompanied by an adult and without travel documents (tickets) shall be transferred by authorized persons at the nearest station to an employee of the internal affairs bodies. 

A passenger who is accompanied by a child under the age of 10 under a free or children's travel document (ticket) shall have an original document confirming the age of the child (a birth certificate, or an ID document of the child, or an ID document of one of the parents, in which there is a note about children), and present it to an authorized person when boarding the train and en route. 

A children's travel document (ticket) is included in the category of special rate tickets. The presentation of the original document confirming the age of the child (a birth certificate, or an ID document of the child, or an ID document of one of the parents, in which there is a note about children) is also required when issuing a travel document (ticket) at a ticket office (in accordance with Clause 9 Part 4 of the Rules). 

ATTENTION! The above requirements of the Rules are developed in accordance with the legislation: 

The Law of the Republic of Belarus “On State Social Benefits, Rights and Guarantees for Certain Categories of Citizens” 

Provisions on the procedure for submitting documents, on the basis of which the right to state social benefits, rights and guarantees is exercised by certain categories of citizens, approved by the Resolution of the Council of Ministers of the Republic of Belarus dated 12/13/2007 No. 1738 (hereinafter referred to as the Provision). 

In accordance with Clause 2 Sub-Clause 2.20 of the Provision, the original of a birth certificate (an ID document) or an ID document of one of the parents, in which there is a note about the children, may be presented.