The Strait of Hormuz exposure behind the Brent move

Passage broke down in February

On 28 February 2026, after US and Israeli strikes on Iran, the Revolutionary Guard forbade passage through the Strait of Hormuz, boarded and attacked merchant ships, and laid mines in the shipping lanes. Tanker traffic fell close to zero. Brent passed $100 a barrel on 8 March for the first time in four years and peaked at $126. It became the largest disruption to world energy supply since the 1970s.^[1]

Six months on, normal passage has not been restored. A sixty-day memorandum signed in Islamabad on 17 June cleared the stranded backlog and moved about 374 million barrels out of the Gulf, roughly 6.1 million barrels a day against 2.3 million during the blockade. That is about 40% of the 15 million barrels a day of crude Hormuz carried before the war, and more than half of it moved in the first three weeks. The window expired on 17 August with no agreement, no extension, and no talks under way. Brent crossed $90.^[2]

The flow that did not come back

Before the war, EIA counted 21.6 million barrels of oil a day through Hormuz in the fourth quarter of 2025, about a fifth of everything the world consumes, and 10.5 billion cubic feet a day of LNG, most of it from Qatar. Between 120 and 140 vessels made the transit daily.^[5][3]

By the second quarter of 2026 those prints were 4.9 million barrels a day and 0.8 billion cubic feet. In the week of 10 August there were 73 transits, down from 91 the week before. By 16 August the count was three vessels in a day. About 520 commercial ships remain inside the Gulf, and Kpler estimates six to eight weeks to clear that backlog once the lanes are demined, work that has not started. Iranian exports through the strait are down 94%, while the other Gulf producers hold near 3 million barrels a day, much of it moving on shuttle tankers to transfer points outside the strait.^[5][4][2]

The waterway has split into two managed lanes: a US-escorted corridor and a northern route used by Iranian- and Chinese-linked vessels running with their transponders switched off. Bypass pipelines carry a fraction of the flow and sailing around adds weeks and cost, with no equivalent path for the stopped volume.^[4]

The print the market already publishes

EIA’s August energy-security tables are the official quarterly record of that collapse. Oil through Hormuz averaged 21.6 million barrels a day in the last quarter before the war, 14.9 million in the first quarter of 2026, and 4.9 million in the second. LNG through the same water fell from 10.5 billion cubic feet a day to 0.8. EIA notes that AIS signals on the strait have been unreliable since the end of February, and still publishes a count by supplementing tracker data with origin, destination and route analysis.^[5]

A chokepoint hedge can settle on throughput, counted against a stated baseline. Brent crossed $100 in March, peaked at $126 and traded back toward $90 by August while the volume stayed a fraction of normal and the lanes remained mined.^[1][2] Flat price tracks the world’s expectation of supply. The barrels that cleared the strait are a different series.

Charterers and idle hulls

A charterer holds a fixture that assumes a transit, and a refiner holds a crude slate assembled from Gulf grades. An industrial buyer holds supply contracts with dates written into them. Partial passage leaves the cargo intact; it arrives late, by a longer route, or not at all, and the buyer settles the difference in cash.

The costs are war-risk premium on every voyage, additional bunkers and ballast days when a vessel routes around the strait or transfers to a shuttle outside it, waiting time, demurrage and detention while a ship holds position, late-delivery penalties, and replacement barrels bought in whichever regional market is short. Shipowners carry the mirror image: idle tonnage, crew risk, and hulls stuck on the wrong side of the lanes, which was about 520 vessels when the truce expired.^[4]

Brent, freight, and war-risk

Hedging a chokepoint with crude futures is a bet on the correlation between a global price and a local passage. Brent repriced twice over while transit counts stayed a fraction of normal. Flat price tracks the world’s expectation of supply, netted against spare capacity elsewhere and demand destruction. A named vessel clearing the strait in a given week is a different print.^[1][2]

Route-based tanker contracts settle against published rate assessments for benchmark voyages, so they capture the level of freight without capturing a specific vessel’s waiting time, a reroute, or a fixture that could not be performed at all.

War-risk hull cover for a Hormuz transit ran a fraction of one percent of insured value before the crisis and now runs 7.5 to 10%, as much as $10 million on a $100 million tanker for a single passage. The Lloyd’s Market Association notes that cover remains available in London and that owners are declining to sail on safety grounds.^[3] The policy responds to loss, damage and detention of the ship. Reduced vessel availability, longer voyages, delay and fuel can exceed the premium itself. Owners pay a larger premium as the risk rises, and still bear the cost of not sailing.

A desk can be flat crude and still carry Hormuz risk through freight commitments, insurance cost, delivery obligations and regional basis, none of which settle against Brent.

A variable that can be counted

Access over the last six months has been partial and vessel-specific, split between an escorted corridor and a northern route run with transponders off, with daily transits falling from 120 to 140 before the war to 73 in one week of August and three on a single day.^[4] The measurable variable is throughput: the number of qualifying transits through a defined waterway over a defined window, against a stated baseline, or the barrels EIA already prints each quarter.

Third parties maintain that count. Route authorities issue notices, governments publish notices to mariners, and ship-tracking providers record which hulls moved where and when; dark vessels show up as an absence from a counted record. A contract can name the route, the vessel class, the window and the baseline, and pay when counted transits fall below a stated share of it. Basis remains: an individual vessel can be moving while the aggregate count is depressed, or the reverse. It narrows as you draw the vessel class and window closer to the fixtures at risk.

Discrete structures these contracts bilaterally for trading desks, charterers and businesses whose delivery obligations depend on a route. If part of your book assumes a waterway keeps working, price a quarter at 4.9 million barrels a day.