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Autonomous Systems: Land & Sea
13JUN

Kpler logs three ships a day in 'open' Hormuz

2 min read
11:07UTC

Kpler counted exactly three transits on each of 22, 23 and 24 July. CENTCOM's formal position is that the Strait of Hormuz remains open for transit.

TechnologyDeveloping
Key takeaway

Three independent trackers put Hormuz traffic at a fraction of pre-war levels while CENTCOM calls it open.

Kpler, the maritime data provider, recorded exactly three vessel transits through the Strait of Hormuz on each of 22, 23 and 24 July, down from more than 20 a day before 15 July⁠1. CENTCOM's formal position is that the strait remains "open for transit".

Both statements can be true at once, and the gap between them is the thing worth understanding. Hormuz is 33km wide at its narrowest and carries about a fifth of the world's seaborne oil; transit passage through it is a right in international law that no naval force has formally revoked. Whether a master exercises that right depends on his charterer, his crew and his underwriters, none of whom are bound by CENTCOM's characterisation. Kpler's count includes vessel-level detail, among them the very large crude carrier New Giant carrying about two million barrels of Basrah crude for China⁠2.

Two other providers reach the same place by different routes. S&P Global counted 40 vessels across 17 to 19 July, about 13 a day, roughly half the previous week's rate. Lloyd's List put tanker and gas-carrier movements specifically at 30 in the week to 20 July against 90 in the week to 13 July, part of the 66% weekly fall we reported on 21 July. Saul Kavonic of MST Marquee, on the record, puts flows at about 15% of pre-war levels⁠3. Three commercial datasets built for paying clients rather than for public argument agree on direction and on magnitude.

The insurance market reached this conclusion first and has not revisited it. War-risk rates on Hormuz transits were repriced in mid-July, when the broker Marcus Baker of Marsh quoted them against a count of eight vessels a day, and they have held at that level while physical traffic fell to three. Underwriters priced a closure the traffic has since caught up with. The exposure now sits in what has not been priced: a single mine strike or boarding in the Larak-Qeshm corridor, the route vessels use to stay outside CENTCOM's written blockade order, could push mainstream insurers to withdraw cover rather than reprice it, which would close the strait commercially without any government declaring it closed.

Deep Analysis

In plain English

The US military says the strait of Hormuz, the narrow waterway through which much of the world's oil passes, is "open for transit". But three separate companies that track ship movements say otherwise. Kpler recorded just three ships a day passing through between 22 and 24 July, down from more than 20 a day before 15 July. S&P Global counted about 13 ships a day in a similar recent stretch, roughly half the week before. In practice, almost nobody is sailing through, whatever the official language says, because the insurance cost of doing so has become too high for most shipping companies to accept.

Deep Analysis
Root Causes

"Open for transit" and "commercially viable to transit" are two different claims, and the gap between them is what three trackers are actually measuring. CENTCOM's statement addresses the first, whether the US Navy will contest passage; the P&I clubs, the insurers that underwrite almost all commercial shipping, address the second, and they set premiums based on assessed risk of loss, not on any government's characterisation of the strait's status.

Once those premiums cross a threshold where insurance cost exceeds freight margin, as the current range does for many operators, rational shipowners divert regardless of what CENTCOM says, because the decision is made in a London or Scandinavian underwriting office, not in Washington or Tehran.

What could happen next?
  • Meaning

    A near-90% collapse in daily transits despite an "open" designation shows insurance markets, not naval statements, are setting the real terms of access to Hormuz.

  • Consequence

    Sustained traffic collapse compounds the Cape of Good Hope diversions already under way, adding weeks to voyage times for cargo bound for Europe and Asia.

First Reported In

Update #162 · Munitions, not Iran, halted US bombing

Baird Maritime (citing Kpler)· 26 Jul 2026
Read original →
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Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Editorial standards.