This thesis delves into the realm of monitoring and calculating costs within production activities, seeking to advance the field of cost accounting through rigorous research. The introduction provides a clear outline of the research's objectives and contribution. In subsequent chapters, the thesis defines fundamental concepts, including cost accounting, cost sharing, and distribution techniques based on natural properties and effects. The study examines diverse cost distribution methods, encompassing factors like the amount of effects, functions, capacity utilization, and allocation based on HSFI, IAS 2, and proprietary accounting policies. Additionally, it analyzes cost allocation concerning the basis of calculation, time of occurrence, and significance for business decisions, emphasizing the necessity of accurate accounting documents for expense tracking. Furthermore, the thesis scrutinizes the meticulous recording of expenses in business books, with a particular focus on accounting monitoring in production activity and cost occurrence by natural types. Detailed records of product costs and periodic expenses are analyzed, along with various types of calculations such as pure division, equivalent number-based, and related products.