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Hormuz Watch

Tanker movement through the world's most important oil chokepoint: baseline, conflict disruption, and the current transit picture.

Read this page as the barrel count behind the price: the Strait of Hormuz carries roughly one-fifth of the world's petroleum liquids, and every transit number here is a proxy for how much of that supply is actually moving. Each bullet carries its vintage, so read the wartime vessel counts against the pre-war baseline of about 20 to 21 million barrels per day, the US Energy Information Administration (EIA) figure for the first half of 2025.

Hormuz is the world's main sour export artery, and when it closes, the sour barrels Western Canadian Select (WCS) competes with disappear first, which is why Canadian differentials tightened as the war cut Gulf flows. Fewer Iranian, Iraqi, and Saudi sour barrels reaching Asia and Europe forces buyers onto substitute grades, bidding up Mars and other Atlantic Basin sours alongside WCS. If Hormuz transits normalize, the returning sour supply is the fastest way Canadian differentials soften again.

Updated September 23, 2026 · refreshes weekly

Baseline: what normal looked like

• EIA estimated oil flows through the Strait of Hormuz averaged 20.9 million b/d in the first half of 2025, roughly 15 million b/d of crude oil and condensate plus about 5.5 million b/d of refined petroleum products.
  Data: H1 2025; accessed 2026-09-23 Talk Markets (citing EIA)
• IEA estimated about 20 million b/d of crude and products moved through Hormuz in 2025, roughly 25% of global seaborne oil trade and about 20% of world petroleum liquids consumption.
  Data: 2025; accessed 2026-09-23 IEA (via Speed Commerce / Newshashtag)
• Of the Hormuz total, nearly 15 million b/d was crude oil, about 34% of all global crude oil trade in 2025; roughly 80% of the oil was destined for Asian markets.
  Data: 2025; accessed 2026-09-23 Energy Prices Today (citing IEA)
• Destination split of Hormuz crude in 2025: China ~25%, India ~19%, Japan ~13%, South Korea ~11%, other Asia ~17%, Europe ~9%, US ~3%; China and India together took 44% of flows.
  Data: 2025; accessed 2026-09-23 Energy Prices Today (citing IEA)
• Saudi Arabia is the dominant single-country contributor to Hormuz crude flows, about 38% or roughly 5.5 million b/d; Iraq, Kuwait, the UAE, Qatar and Iran make up the rest.
  Data: 2025; accessed 2026-09-23 Speed Commerce (citing EIA/IEA)
• EIA estimated one-fifth of global LNG trade moved through Hormuz in 2024, primarily Qatari cargoes, IEA's February 2026 factsheet put it at almost 20% of global LNG exports.
  Data: 2024 (EIA); Feb 2026 (IEA factsheet); accessed 2026-09-23 EIA Today in Energy (via GitHub essay)
• US crude and condensate imports through Hormuz were about 7% of total US crude and condensate imports in 2024 and about 2% of US petroleum liquids consumption.
  Data: 2024; accessed 2026-09-23 EIA Today in Energy (via GitHub essay)
• Saudi Arabia and the UAE have pipelines capable of bypassing the strait, but together they could provide only about 4.7 million b/d of bypass capacity, a fraction of normal ~21 million b/d traffic.
  Data: EIA estimate current through 2026; accessed 2026-09-23 Talk Markets (citing EIA)
• Saudi Arabia's East-West Pipeline carries crude from the kingdom's eastern producing region to Yanbu on the Red Sea, allowing Saudi oil to reach water without passing through Hormuz; it has become the main bypass artery during the current conflict.
  Published ~Sep 16, 2026; accessed 2026-09-23 Talk Markets

The current escalation (reported)

• The current war was triggered February 28, 2026 by joint US and Israeli strikes on Iran; Iran responded by closing commercial access to Hormuz through vessel attacks and sea mining.
  Reported Sep 2026; accessed 2026-09-23 InvestingLive
• As of September 20, 2026, US Central Command said its forces had redirected 109 commercial vessels to enforce compliance with the US maritime blockade on traffic to and from Iranian ports, a blockade resumed July 14, 2026.
  Sep 20, 2026; accessed 2026-09-23 Defcon Level (citing CENTCOM)
• The Joint Maritime Information Center listed three Hormuz attacks in Update 098 (covering March 1–September 20, 2026) and set the regional maritime threat level at SEVERE.
  Sep 20, 2026; accessed 2026-09-23 Defcon Level (citing Joint Maritime Information Center)
• On September 1, 2026, a commercial tanker was struck by at least three unknown projectiles while completing an outbound Hormuz transit about 17 nautical miles east of Khasab, Oman; no casualties were reported. A second reported tanker strike nearby (Saudi-flagged Sidr) was carried as reported but unconfirmed by that source.
  Sep 1, 2026; accessed 2026-09-23 GeoBit AI
• Between September 16 and 18, 2026, three tankers were struck in the strait; the Togo-flagged product tanker Trend was hit September 16 near Khasab and caught fire before the crew extinguished it. Iran's Revolutionary Guard claimed the Trend attack, saying it was an illegal transit attempt, and warned any unauthorized passage would face 'destruction'.
  Sep 16–19, 2026; accessed 2026-09-23 MarineRadar
• A UKMTO security warning dated September 17, 2026 covered an attack 16 nautical miles northeast of Khasab, Oman; the targeted vessel's crew were confirmed safe with no environmental impact.
  Sep 17, 2026; accessed 2026-09-23 InvestingLive (citing UKMTO)
• UKMTO reported September 21, 2026 that an inbound tanker transiting the strait was struck by an unknown projectile; two crew members suffered minor injuries, the vessel continued under its own power, and no environmental impact was reported. An investigation is underway; the vessel's name and flag were not released.
  Sep 21, 2026; accessed 2026-09-23 MarineLink (citing UKMTO)
• UKMTO reported a second September 22 incident in which an LNG tanker was said to have been struck by an unknown projectile in the strait, with no injuries, the second attack reported that day.
  Sep 22, 2026; accessed 2026-09-23 London Channel News (via Qatar Tribune / DPA, citing UKMTO)
• UKMTO issued an advisory after the September 21 strike urging vessels operating in the area to transit with caution and report suspicious activity to authorities.
  Sep 21, 2026; accessed 2026-09-23 Nation Press (citing UKMTO)
• On September 20, 2026, the US Mission in Saudi Arabia said US government employees need special authorization for official and personal travel to Taif and Yanbu.
  Sep 20, 2026; accessed 2026-09-23 Defcon Level (citing US Mission Saudi Arabia)

Now vs normal: the transit picture

• EIA figures show Hormuz oil flows fell from 21.6 million b/d in Q4 2025 to just 4.9 million b/d in Q2 2026, while Bab el-Mandeb flows rose from 5.4 to 8.1 million b/d, a major rerouting of the global oil transportation system.
  Data through Q2 2026; accessed 2026-09-23 Talk Markets (citing EIA)
• Fewer than 10 commodity vessels per day transited Hormuz over the weekend of September 19–20, 2026; on Sunday seven vessels transited, including three Iranian-linked oil products tankers exiting the strait.
  Weekend of Sep 19–20, 2026; accessed 2026-09-23 MarineLink (citing Kpler)
• Crossings through the strait fell to just four vessels on September 16, 2026, the same day as the first of that week's attacks.
  Sep 16, 2026; accessed 2026-09-23 MarineRadar
• Recent tracking shows commodity-carrying Hormuz transits averaging roughly 10 vessels per day versus a pre-war baseline of around 85–90; throughput has been reported as low as ~7% of normal in some periods.
  Analysis published ~Sep 21, 2026; accessed 2026-09-23 LinkedIn analysis (S&P Global / tracking data)
• IEA's September 2026 Oil Market Report said more than 10 million b/d of Gulf output remained shut in amid security risks; cumulative supply losses since February exceeded 507 million barrels of observed inventory draws.
  Data through Aug 2026; report Sep 11, 2026; accessed 2026-09-23 Namibia Daily News (via Xinhua, citing IEA September OMR)
• The White House signed H.R. 5334, the Graham Sanctioning Russia and Iran Act of 2026, into law September 18, 2026, expanding sanctions and tariff authority relating to Russia and Iran and the shadow tanker system supporting Russian energy exports.
  Sep 18–19, 2026; accessed 2026-09-23 The DeepDraft SITREP (Sep 19, 2026)

Freight, insurance, and price knock-ons

• VLCC rates on West Asia–China routes hit a record $1.2 million a day, more than doubling since late August; Energy Aspects' Amrita Sen warned surging shipping costs could push delivered crude in Asia toward $150 a barrel.
  Reported Sep 23, 2026; accessed 2026-09-23 PressTV (citing Financial Times / Braemar)
• The Baltic VLCC time-charter average rose from ~$198,000/day in July to ~$449,000/day in the first half of September, reaching ~$722,946/day by September 18, 2026, versus ~$79,700/day in mid-September 2025.
  Sep 18, 2026; accessed 2026-09-23 GeoTrends (citing Baltic Exchange)
• War-risk insurance premiums were revised from peacetime levels of 0.5–1% of hull and machinery value to approximately 10%, millions of dollars in added cost per VLCC voyage, passed through to charterers.
  Published ~Sep 17, 2026; accessed 2026-09-23 Nile1 (citing Vortexa freight analysts)
• US Gulf–China VLCC rates were reported at $400,000 per day and Middle East Gulf spot rates at $1.25 million per day in late September 2026.
  ~Sep 22, 2026; accessed 2026-09-23 TradeWinds News (citing BRS Shipbrokers)
• IEA projects 2026 world oil supply averaging 100.7 million b/d, down 5.7 million b/d year-on-year, with full recovery of Middle East supplies deferred until 2027; global oil demand is forecast to fall 2.5 million b/d in 2026.
  Report Sep 11, 2026; accessed 2026-09-23 IEA Oil Market Report September 2026
• Brent traded near $104 a barrel in the week of September 11, 2026, its highest since July, as US–Iran hostilities renewed and Houthi–Saudi fighting intensified in the Red Sea.
  Sep 11, 2026; accessed 2026-09-23 Rigzone (via Bloomberg)

For the WCSB book, Hormuz is the supply-side risk premium inside every WCS print. Vessel counts and the EIA's quarterly volume series tell you whether the chokepoint is loosening before the price does. The moment Gulf sour barrels flow freely again, expect the bid under Canadian heavies to fade with them.

Standing watch

What the daily feed updates on this page.

• Daily/weekly Kpler and Vortexa Hormuz transit vessel counts
• UKMTO incident warnings and advisories for the strait
• CENTCOM and JMIC maritime threat updates
• EIA World Oil Transit Chokepoints quarterly volume series
• IEA Oil Market Report monthly for supply/demand revisions
• VLCC rates on Middle East–China routes (Baltic Exchange / Braemar / BRS)
• War-risk insurance premium levels for Gulf transits
• US–Iran diplomatic signals (negotiation status, blockade enforcement actions)

Gaps

• Day-to-day vessel transit counts change constantly; Kpler/Vortexa snapshots cited are date-specific.
• The Sep 21 struck tanker's name and flag were not released by UKMTO at time of reporting.
• Whether the Sep 22 LNG tanker strike is independently confirmed beyond UKMTO/DPA reporting.
• EIA's next scheduled World Oil Transit Chokepoints update date was not found.
• Exact current daily barrel flow (vs vessel counts), trackers report vessels; EIA's quarterly volume series lags by months.

Sources