The analysis of natural gas consumption trends shows that gas consumption in Croatia is extremely seasonal, with high fluctuations during peak consumption. The objective of the research was to show the importance of each part of the system in providing flexibility. By analyzing the movement of gas flow, data was obtained on the contribution of each part of the system to the overall flexibility. The flexibility factor of natural gas imports at interconnection points, based on flexible supply contracts, was negative due to higher imports in the summer months. Additionally, production has been steadily declining, so this source of flexibility has less opportunity to provide a significant amount of flexibility. The LNG terminal as a new gas import point into the system, has not yet been considered a possible source of flexibility. The LNG volumes from the new terminal were analyzed using an analogous methodology. The results of the research showed the analysis of the flexibility of each segment of the gas system and the movement of flexibility before and after the introduction of LNG into the market. Finally, the novelty of this research could be described as the definition of flexibility calculations for each part of the natural gas system.