Purpose – To analyze the impact on total cost by inventory control methods under the influence of seasonal demand. The purpose will be answered with following research questions:

1. What inventory control methods can be used when there is seasonal demand?

2. What is the impact of inventory control methods on total cost under the influence of seasonal

   demand?

Method – The study was conducted as a case study and the empirical data was collected through interviews and document study. Both of these contributed to the basis for the analysis and for the calculations in the test of the study. Literature study was conducted and included theories for inventory control methods to answer the first research question, as well as formulas for the methods used to answer the second research question.

Findings – It appears from the study, the inventory control methods that can be used when there is seasonal demand and during current planning environment is periodic ordering system and cycle service method. These have been tested further in the study. Seasonal index was considered an important method since it dimensions demand which to a high degree regulate the inventory levels and thereby the result of the inventory control methods. Further the study compares none theoretical inventory control methods and theoretical inventory control methods impact on total cost. It is shown that carrying costs, as a part of total cost, can be reduced by 25% during the peak season and 62% during off-season. This without changing the deliverability. Alternatively, the deliverability can be increased by 10% by using inventory control methods without increasing the total cost of the inventory.

Implications – The theoretical contribution of the study is that it has increased the knowledge concerning inventory control methods when there is seasonal demand, and the possible results they might bring. The empirical contribution of the study is that companies can use the study as an indication of the economic benefits and motivation for implementing theoretical inventory control methods.

Limitations – The tested inventory control methods did not alter the ordering cost, which to a high degree can have an impact on the total cost. The study also shows a possible impact on the inventory control during the current planning environment. If the planning environment changes, the result of the study can be different.