This paper reviews the EU Solidarity Contribution that was recently introduced by the Council Regulation on Emergency Intervention to Address High Energy Prices and proposes a more proportional alternative. It is argued that the legitimacy of the EU Solidarity Contribution might be disputed. The role that Member States have played in driving up energy prices by filling their natural gas storages much more than the EU’s filling trajectory prescribes raises questions as to whether the EU Solidarity Contribution could be in conflict with the proportionality principle and whether all formal requirements of Article 122(1) Treaty on the Functioning of the European Union (TFEU) have been fulfilled. Furthermore, it is argued that the EU Solidarity Contribution may compromise protection of investments under international investment agreements (IIAs) as the current design might entail elements that violate fair and equitable treatment (FET). As an alternative to the EU Solidarity Contribution, the article proposes the following. First, a legal commitment should be introduced for fossil fuel companies to invest 100% of their realized excess profit for decarbonizing the economy under the threat of taxing away those excess profits in their entirety should it become apparent that the investments are not actually realized. Second, in lieu of the EU Solidarity Contribution, the incidental financial support measures for vulnerable households could be financed with the excess (windfall) revenue collected from Value Added Tax (VAT) and excise due to the high inflation in the EU in 2022.