Idemitsu Kosan's net profit attributable to shareholders for the three months to June came to ¥217.5bn, up 696% from ¥27.3bn a year earlier. Revenue rose 23.8% to ¥2.27tn and operating profit swung to ¥307.5bn from an operating loss of ¥4.0bn in the same quarter last year. The company confirmed on August 14 that Deloitte Touche Tohmatsu completed its review of these figures with no changes from the results first disclosed on August 7.
| Metric | Q1 to June 2025 | Q1 to June 2026 | Change |
|---|---|---|---|
| Revenue | ¥1.84tn | ¥2.27tn | +23.8% |
| Operating profit | -¥4.0bn | ¥307.5bn | Swing from loss (n/a) |
| Pre-tax profit | ¥21.5bn | ¥316.9bn | n/a |
| Net profit attributable to parent | ¥27.3bn | ¥217.5bn | +696.0% |
The swing was almost entirely a refining story. Idemitsu's fuel oil segment posted ¥293.8bn in segment profit, up ¥312.6bn from a year earlier, as rising crude prices widened a timing gap between when the company buys crude and when it sells refined product. The company attributes the longer lag partly to a worsening security situation in the Middle East, which has lengthened tanker voyage times and stretched out the period before crude costs hit the books; once oil prices climbed from March onward, that lag turned into a large gain rather than a drag.
Other segments moved on a smaller scale. Basic chemicals profit rose ¥2.1bn to ¥0.1bn despite lower sales volumes, helped by a positive inventory effect. High-performance materials profit fell 15.6% to ¥14.5bn as a one-off gain in the lubricants business from a year earlier did not repeat. Power and renewable energy swung to a ¥1.3bn segment loss on scheduled maintenance and a generation problem at Toa Oil. The resources segment, covering oil, gas and coal, posted ¥18.9bn in profit, up 47%, on higher Vietnamese condensate volumes and coal prices.
The quarter also marks Idemitsu's switch to International Financial Reporting Standards, with early adoption of IFRS 18, the new standard governing how companies present and disclose results. Under the transition, recognized as of April 1, 2025, the group booked a ¥90.0bn goodwill impairment tied to its fuel oil business, since IFRS goodwill is no longer amortized but tested annually for impairment rather than only when trouble signs appear.
On the balance sheet, Idemitsu bought back 19.8mn shares for ¥27.7bn during the quarter under a board-approved program capped at 43mn shares and ¥30bn, then cancelled 65.5mn treasury shares on April 30, 2026. Capital surplus stood at ¥203.5bn and treasury stock at ¥28.6bn at quarter-end. Total assets rose to ¥6.06tn and the parent equity ratio slipped to 27.2% from 27.8%, with the net debt-to-equity ratio ticking up to 1.17 from 1.03.
Despite the outsized quarter, Idemitsu has not touched the full-year guidance it set on May 12, 2026: parent net profit of ¥75.0bn, down 57.4% from the prior year, alongside an annual dividend held flat at ¥36.00 per share. That full-year figure sits well below the ¥217.5bn already booked in this single quarter, a gap that signals management does not expect the current pricing tailwind to hold for the rest of the year to March 2027.