What the US-Iran MOU actually says about Strait of Hormuz passage

The memorandum of understanding signed in Muscat on Jun 24, 2026 is the reason ships are moving through the Strait of Hormuz today. It is also the reason the status on this site reads RESTRICTED rather than OPEN. Both facts follow from the same document, and the gap between them is where most of the confusion sits.

As of Jul 7 the arrangement is on day 14 of 60. Transits are fee-free. They are not unconditional: Iran continues to designate which lane a vessel uses, and it enforced that designation as recently as Jul 5, when six merchant ships were turned back from the Omani corridor into Iran-designated lanes. No damage was reported; transit times rose roughly four hours.

This piece is a close reading of what the memorandum actually commits the parties to — what is binding, what is discretionary, and what was deliberately left out. Treat every figure here as illustrative sample data drawn from the sources listed at the end.

What was signed in Muscat

The document is a memorandum of understanding, not a treaty and not a ceasefire. That distinction is not pedantic. An MOU records an understanding between parties; it does not create obligations enforceable in any court, and neither signatory submitted it for legislative ratification. Its force comes entirely from the parties' willingness to keep observing it.

The war that began Feb 28, 2026 is not formally ended by the memorandum. Nothing in the text addresses hostilities outside the strait, sanctions architecture, or the nuclear file. It is a narrow maritime arrangement bolted onto an unresolved conflict, which is why analysts have described it as a de-escalation instrument rather than a settlement.

An MOU is a promise to behave for sixty days. It is not a legal regime, and no underwriter is pricing it as one.

Marine insurance market commentary, Jul 2026

The fee-free window mechanics

Between Feb 28 and Jun 24, Iranian authorities levied a transit charge on vessels using the designated lanes. The memorandum suspends that charge for the duration of the window. It does not abolish it, and it does not characterise the charge as having been unlawful — a point Iranian officials have emphasised and US officials have declined to contest in writing.

The suspension applies to the fee only. Vessels still file a routing request through the Iranian coordination channel established in March, still receive a lane designation, and still carry the administrative overhead that came with it. Operators describe the paperwork burden as unchanged; what disappeared was the invoice.

Daily transit counts have recovered from the trough but not to baseline. The 2024 average of 20 million barrels per day — roughly a fifth of world petroleum liquids consumption — remains the reference point against which every recovery figure is measured, and current volumes sit well below it.

The routing carve-out Iran retained

This is the single most consequential clause and the least reported. Iran retains what the text calls routing designation: the authority to assign each transiting vessel to one of the two designated lanes and to require adherence to that assignment. The US did not accept this authority. It agreed not to challenge it operationally for 60 days. Those are different things, and the memorandum keeps them apart on purpose.

The practical consequence surfaced twice in the first fortnight. On Jul 1 a container ship ran aground near Larak Island after transiting a route Iran had not approved; salvage is under way and both designated lanes remain usable. On Jul 5 six ships attempting the Omani corridor were turned back. Neither event breached the memorandum, because the memorandum does not give vessels a right to choose their own route.

Verification, such as it is

There is no inspection regime, no joint monitoring body, and no third-party observer mission. Verification rests on three thin mechanisms, none of which produces an authoritative record.

• Self-reporting by transiting operators to their flag states and underwriters, which is voluntary and inconsistently filed.
• AIS track data, which is degraded across the region by persistent GPS interference and by vessels operating with transponders off.
• A bilateral consultation channel hosted by Oman, which can convene on request but has no fact-finding authority and publishes nothing.

The practical effect is that disputes about compliance are argued from incompatible datasets. When Iran says no vessel was interfered with and an operator says it was diverted, both can point to their own records and neither can be checked against a common source.

The mine problem sits outside the text

Mines reported in the approach corridors since March are not addressed. The France-Oman clearing initiative was rejected by Iran in June, before the memorandum, and the memorandum does not revive it. Fee-free passage through a corridor that has not been swept is a commercial improvement, not a safety one, and war-risk underwriters have priced it accordingly.

Snap-back and what triggers it

Either party may suspend its own undertakings on notice. The text specifies notice, not cause — there is no defined list of violations and no adjudication step. In practice this means the window can close on a political decision rather than a documented breach.

1. A party notifies the other through the Omani channel that it is suspending its undertakings.
2. A short notice period runs, during which vessels already committed to transit are expected to be allowed through.
3. The fee suspension lapses and the US escort suspension lapses, each independently of the other.
4. The arrangement reverts to the pre-Jun 24 posture unless a new understanding is reached.

Because the two suspensions lapse independently, a partial unwind is possible: Iran could reinstate fees while US escorts remain suspended, or the reverse. Chartering desks have been writing contingency clauses against both, which is one reason freight rates have stayed volatile despite the calmer operating picture.

What happens on day 60

Nothing automatic. Counting from Jun 24, day 60 falls on Aug 22, 2026, and the text contains no rollover provision. Absent a new agreement, the fee suspension simply ends and the pre-memorandum arrangement resumes — including the transit charge, which was never abolished.

What the MOU does not cover

A short list of the omissions that matter most, because each one is a place where the current calm can fail without anyone breaching anything.

• The legal status of the strait. Neither party's position on transit passage rights is stated, conceded, or reserved in the text.
• Mine clearance in the approach corridors, which remains unagreed and unscheduled.
• The Omani alternative lane, which Iran declared void and the memorandum does not mention.
• Insurance and war-risk premiums, which are set by the market and were not part of the negotiation.
• Vessels flagged to states that are party to neither side's arrangements, whose treatment is left to Iranian discretion.
• Any conduct outside the strait and its approaches, including the wider hostilities that began Feb 28.

The memorandum bought sixty days of cheaper, calmer transit without resolving a single underlying question. That is a real achievement for shipping and a fragile one. Our daily status page tracks the operating picture at /, transit and volume series are at /data, and the full sequence of events since February is at /timeline.