What caused Japanese refinery utilization rates to rise above 70% for the first time since March?

Japanese refinery utilization rates rose above 70%—reaching 77.3% in the week to May 2 and 73.3% in the week to May 9—due to increased processing of crude oil released from government stockpiles (equivalent to ~75 days of consumption, the largest release ever) and alternative supplies sourced from the U.S., the Caspian region, Latin America, and a cargo of non-sanctioned Russian oil, following supply disruptions caused by the U.S.-Israeli war with Iran and the near-closure of the Strait of Hormuz.

How are Idemitsu Kosan and Cosmo Energy responding to the supply situation, and what are their outlooks for Gulf oil access and refinery operations?

Idemitsu Kosan and Cosmo Energy Holdings—the second- and third-largest Japanese refiners—are sourcing Gulf crude that bypasses the Strait of Hormuz and targeting refinery utilization rates above 90% this fiscal year; Idemitsu expects the Strait of Hormuz to reopen between July and September and Dubai oil prices to return to pre-war levels by March 2027, while Cosmo expects Gulf crude production to normalize in August and procurement to stabilize from September onward.

Japan Refinery Runs Climb to Over 70% on Alternative Supply, Stockpile Releases

May 12, 2026

Japanese refineries boosted utilization above 70% using stockpiles and alternative crude amid Middle East tensions. Idemitsu Kosan and Cosmo Energy project market normalization by fiscal year-end 2027.

reuters

2026-05-12

Japan Refinery Runs Climb to Over 70% on Alternative Supply, Stockpile Releases

Japan Refinery Runs Climb to Over 70% on Alternative Supply, Stockpile Releases

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