Storage levels at late-August seasonal low
European underground gas storage is entering the final phase of the filling season with inventories at a 13-year seasonal low. Inventories are also at the lowest level for late August since 2013, which raises the amount of gas the region needs to inject before the 2026/27 heating season.
EU underground storage facilities hold around 69.2bn cubic metres. That leaves inventories 14.3bn cubic metres below their level at the same stage of 2025.
Storage sites are about 63.28% full, compared with roughly 76% a year earlier. Stocks are also 17.24% below the five-year average, leaving Europe with a smaller buffer as the summer injection period moves into its last months.
Injection pace and late-season procurement pressure
The inventory gap increases the importance of injection rates during September and October. About 39bn cubic metres has been added to European inventories since injections began in April.
Net additions during August are running at their weakest pace for the month in six years. Estimates suggest that as much as another 68bn cubic metres may need to be injected before winter to rebuild inventories toward required levels.
The EU rules require storage facilities to reach 90% between 1 October and 1 December. Countries facing difficult filling conditions can deviate from that target by as much as 10%.
Implications for winter supply balance and risk factors
A lower starting point means storage operators and suppliers face a more demanding late-season procurement programme than last year. A key variable will be whether injection rates can accelerate sufficiently without stronger storage demand tightening the wider European gas balance.
A reduced storage cushion also leaves the 2026/27 winter market more exposed to weather conditions, LNG availability, and unexpected supply disruptions. The pace of injections during the remainder of the filling season will therefore shape how comfortable Europe’s supply position is when heating demand begins to rise.
