The Mediterranean Sea is an important shipping market accounting for around 7% of global maritime activity, and 0.5 million b/d of marine bunker fuel demand. The sulphur limit for vessels travelling in the Mediterranean Sea will fall from 0.5% to 0.1% from May 2025, having been adopted at the IMO MEPC 79 meeting in December 2022. Using our proprietary Refinery Supply Model (RSM), this insight explores the impacts arising as a result of the Mediterranean Sea becoming an Emission Control Area in 2025. Key topics covered in the analysis include 1) an assessment of the impacts on marine fuel demand, and which bunker markets will be most affected 2) the impact on marine fuel pricing and refinery yields and 3) how these changes impact product trade flows in the region.