Dark Tanker Transits Dominate Hormuz Since 14 July; Traffic drops to 10 vessels amid Iran-US war escalation

The Strait of Hormuz, through which roughly 20-25% of global seaborne crude passes, has experienced a dramatic collapse in normal tanker traffic since mid-July 2026, with legitimate vessel counts dropping to approximately 10 per day, down from historical flows of 100-150 daily transits. The reduction follows escalating US-Iran military exchanges and reflects both direct shipping attacks and war risk insurance premium spikes that make conventional passage economically prohibitive. Shadow tanker fleets and dark vessels have increased traffic, but they operate at significantly higher cost due to insurance avoidance, ship-to-ship transfer complexity, and transit delays. The UAE has emerged as a critical workaround by moving record crude volumes through Hormuz, but total throughput remains substantially constrained. The blockade's persistence beyond five months without diplomatic resolution raises forward visibility risks for global crude supply.

Oil & gas producers moved most at +9.8% against the market, the direction you would expect from a waterway block. None of the moves cleared the significance threshold. Read the direction as flavour, not signal.

Volatility measures how erratic prices became, a separate signal from the direction of the move.

The reaction peaked around day 11 on average. 4 of 5 sectors reverted inside the window, 1 were still elevated at the close. A reaction that reverts is a shock priced in; one that stays is a re-rating.