ACER: Lower Congestion Levels In 2024 And 2025 Point To A New Equilibrium In The EU Gas Market

ACER publishes today its biennial report on contractual congestion in EU gas markets, covering 2024 and 2025.

ACER finds that contractual congestion eased over the period, pointing to a new equilibrium in the EU gas market following the 2022 energy crisis.

What are the key findings? 

The crisis, followed by the EU’s gradual phase-out of Russian gas, rapidly reshaped the EU gas market. Liquefied natural gas (LNG) imports surged while demand fell sharply, leading to a reconfiguration of cross-border gas flows, with stronger west-to-east and coastal-to-continental flows. 

The optimisation of existing infrastructure and new investments helped absorb the shock. However, parts of the network still face residual congestion, reflecting the market’s continued adjustment to new supply and demand patterns. 

ACER finds that:

• 24 exit/entry sides of interconnection points were contractually congested in 2025 and 23 in 2024 (down from 35 in 2023 and 50 in 2022). 

• Network congestion persisted on key west-to-east routes and selected interconnection points in Southeast Europe.

• Congestion revenues stabilised at EUR 140 million (similar to 2023 levels).

• The capacity surrender scheme (which allows users to return unused capacity for reallocation) surpassed the oversubscription mechanism (offering extra capacity based on expected unused capacity) as the most used congestion management procedure.

Possible ways forward to ease congestion

Stronger transmission system operators' coordination, full application of capacity allocation and congestion management rules, and careful assessment of investment needs where bottlenecks persist could ease congestion in the EU gas markets.

ACER’s results can support national regulatory authorities when deciding whether to apply congestion management procedures.