EU Commission Regulation No. 312/2014 established a Network Code on Gas Balancing of Transmission Networks. These rules stimulate the development of the wholesale gas market by encouraging balance responsible parties to use standardized balancing mechanisms. The balance responsible party is in charge of balancing the group portfolio on daily basis. In order to balance the portfolio, the responsible party can use the available capacities of the transmission system, trade on a virtual trading point or trading platform and has the right to re-nominate the use of the transmission system and the gas storage system. If responsible parties do not balance their portfolios, the system may slip outside the margin of tolerance. The transmission system operator (TSO) then undertakes the balancing action to return the system within the acceptable tolerance limits. Plinacro, as the TSO in the Republic of Croatia, implements the balancing of the transmission system pursuant to EU Commission Regulation No. 312/2014, the Rules on the Organization of the Gas Market and the Transmission System Network Code. In accordance with the Rules on the Organization of the Gas Market, the Croatian Energy Market Operator performs monthly calculation of the daily imbalance charge, trades conducted on the trading platform for TSO activities, the neutrality charge and the charge for deviation from the nominated quantities. The balance responsible party may be entitled to compensation or be liable to pay compensation based on the monthly calculation of the Croatian Energy Market Operator, depending on the value of each charge.