Introduction

Crude oil continues moving through the Strait of Hormuz despite a sharp rise in Iranian attacks during October. Tankers have adapted their operations to sustain flows, even as security risks and shipping costs surged to levels unseen in earlier phases of the conflict.

What Happened

Within 24 hours of the U.S. and Israel engaging Iran, Tehran launched a wave of attacks on commercial ships in the Strait of Hormuz, aiming to disrupt a key global oil chokepoint. Early in the war, exports plummeted nearly 90 percent to 1.8 million barrels per day in March, down from 16 million barrels per day in February, according to Kpler data. However, the U.S. military provided escort and air protection, allowing crude flows to recover over the following eight months. By October, attack frequency hit a peak: at least 30 vessels were struck, 16 seafarers were injured, and confirmed incidents doubled from 15 in September to 30 in the latest month, according to the International Maritime Organization.

Crude prices responded quickly, with the international Brent contract trading above $117 per barrel, just shy of the $118.35 wartime high set in March. Despite the violence, the average daily export through Hormuz in October stood at roughly 11.1 million barrels, only about 2 percent below September levels, showing remarkable resilience.

Why This Matters

The situation highlights how quickly oil supply chains can react to geopolitical shock, and how the industry adapts under pressure. Shipping companies introduced a shuttle system: tankers load at Persian Gulf ports, transit the Strait with transponders off, then transfer cargo to waiting vessels in the Gulf of Oman. This approach kept flows moving, pushing shipments up more than 70 percent since July. However, the method is costly, about 20 percent of the world's supertanker fleet is now dedicated to the shuttle, and freight rates climbed from $249,000 per day in early September to over $900,000 by early October, adding roughly $21 in transportation cost per barrel of crude.

These added costs directly affect Asian refiners, where freight can now represent 20 to 30 percent of the delivered price of oil. Gulf oil producers are responding by chartering their own tankers to move cargo through the strait, seeking to protect market share against Atlantic and U.S. producers. The operation remains heavily dependent on U.S. military air support, as ship safety officials note most operators would not risk the route without fighter jet, helicopter, and drone coverage.

Key Takeaways

  • October saw the highest number of tanker attacks yet, but crude exports held near 11 million barrels per day on average.
  • Freight costs have more than tripled, significantly raising the delivered price of Middle East oil in Asia.
  • The shuttle system has kept oil moving, but at the cost of tying up a fifth of the global supertanker fleet.
  • U.S. military air cover remains the decisive factor in whether tankers risk the Strait at all.
  • Midterm elections and shifting political winds in Washington could alter the level of military support and, by extension, oil flow stability.

Conclusion

While tankers have so far kept crude flowing through the Strait of Hormuz despite intensified Iranian attacks, the margin for error is thin. The industry's shuttle adaptation has prevented a supply collapse, but it comes with steep financial and operational costs. As the political landscape shifts ahead of key elections, the sustainability of these operations will depend heavily on continued U.S. military support and the willingness of producers to absorb escalating risk premiums.