69 Days That Closed the Strait of Hormuz: How $138 Brent, +38% Diesel and 3.3% US CPI Got Made
Strait of Hormus may stay closed indefinitely - Iran plans it to become a permanent law
The Strait of Hormuz is 21 nautical miles wide at its narrowest point. For 69 days now, it has been effectively closed to commercial transit, and almost every dollar-denominated price you care about has moved because of it. Brent peaked at $138 a barrel on April 7. PPI diesel jumped 37.8 percent in a single month. US headline CPI accelerated to 3.32 percent year on year. Approximately 1,500 vessels are sitting in the Persian Gulf right now, unable to leave. This is the story of how a 21-mile waterway changed every print on the macro tape.
What actually happened
This is not the recurring “Iran-might-close-the-strait” story we have been hearing for two decades. This time, it actually happened, and the trigger was a US-Israeli military campaign rather than an autonomous Iranian decision in calm conditions.
On February 28, 2026, the United States, alongside Israel, launched Operation Epic Fury - an air and maritime campaign targeting Iranian command and control nodes, IRGC headquarters, ballistic missile sites, navy ships and submarines, anti-ship missile sites, air defence and military airfields. Iran’s supreme leader, Ali Khamenei, was killed in the initial strikes; his son was appointed successor. Iran responded by counter-striking US bases and Arab states, and by closing the only thing it had unilateral physical control over: the Strait of Hormuz.
The IRGC confirmed the closure on March 2, 2026, with a formal “closed” declaration on March 4. Within a week, the UK Maritime Trade Operations Centre had logged more than a dozen attacks on ships in and around the strait. The Thai bulk carrier Mayuree Naree was hit and burned on March 11, the same day an IRGC Khatam al-Anbiya headquarters spokesperson told the world that not “a litre of oil” would be allowed through. QatarEnergy invoked force majeure on all LNG shipments on March 4. P&I cover from major underwriters was withdrawn from March 5. Maersk, CMA CGM, MSC and Hapag-Lloyd all suspended Hormuz transits. A short-lived US escort program called Project Freedom was suspended after roughly two days of operations.
By early May, the situation had hardened rather than de-escalated. Around May 4 to 7, Iran formally established the Persian Gulf Strait Authority - a new government agency that requires commercial vessels to submit detailed permit applications (covering cargo, crew, ownership, insurance), and which imposes tolls on approved passages through IRGC-designated lanes. Lloyd’s List Intelligence confirmed the authority’s existence after direct communication with the agency. As of May 7-8, approximately 1,500 commercial vessels were holding position inside the Persian Gulf, unable to safely transit out. Roughly 5 percent of pre-conflict transit volumes are still moving. The closure has lasted 69 days and counting.
The geography of the chokepoint
To see why the price reaction is what it is, you need to see the map. The strait is not just narrow - it is asymmetric. Iran sits on the northern shore, Oman on the southern. The IRGC has held operational responsibility for the Persian Gulf since the 2007 reorganization of Iran’s two parallel navies. There are exactly two real bypass routes for crude, and one of them is small.
That asymmetry matters. Roughly 80 percent of Hormuz oil and 90 percent of Hormuz LNG is destined for Asia. China and India together account for about 44 percent of Hormuz crude offtake. China, India and South Korea combined absorb about 52 percent of Hormuz LNG. So a closure does not hit “global energy” in the abstract - it hits Asian buyers first and hardest, which is why JKM (Asian LNG benchmark) has moved more than TTF (European), and why Asian refining margins have been the first to crack.
The transit collapse: 95 to 99 percent
The flow numbers are the cleanest single piece of evidence that this is qualitatively different from a sanctions episode or a tanker incident. Outbound transit dropped 88-99 percent across every relevant cargo class.
Crude oil transit collapsed from approximately 14.95 mb/d to a sliver - roughly 90 percent down. Refined products fell about 88 percent. LNG essentially zeroed - down 99 percent, since Qatar’s Ras Laffan terminal is geographically captive to Hormuz with zero alternative route. Fertilizer-related cargoes (urea, ammonia, sulphur, phosphate) dropped 87 percent through the first weeks per WTO/AXSMarine trade tracking. The only flows still moving are a small number of vessels that have either obtained PGSA permits or are explicitly Iran-aligned cargoes.
To put that into a wider context: Hormuz is not just an oil chokepoint. It accounts for about 50 percent of the world’s seaborne sulphur trade, 34 percent of crude oil, 27 percent of LPG, 25 percent of urea, 19.5 percent of LNG, 18 percent of ammonia, 14 percent of chemicals, and 13 percent of phosphate fertilizer. When you close the strait, you do not just shock the energy complex - you shock the inputs to about a third of the world’s industrial chemistry and a quarter of its food-system nitrogen.
The crude oil math: 20 mb/d in, 2 mb/d out, 9 mb/d shut in
The IEA’s Hormuz tracker reported that oil flows through the strait fell from approximately 20 mb/d (crude plus products) to “well under 2 mb/d” in March. The bypass pipelines plausibly delivered an additional 2.5 mb/d of uplift versus pre-conflict baseline. That math leaves a structural gap of around 15.5 mb/d - the volume of barrels that simply could not leave the Gulf or be replaced from non-Hormuz origin.
That 15.5 mb/d gap forced upstream producers to shut in physical wells - because what cannot leave the Gulf cannot be sold. The EIA’s April 2026 Short-Term Energy Outlook estimates upstream crude production shut-ins of 7.5 mb/d in March, peaking at 9.1 mb/d in April, then easing to 6.7 mb/d in May. To put that in perspective: the entirety of US crude production is around 13 mb/d. The world is shutting in three-quarters of the United States’ worth of crude every month.
This is also why the IEA released 400 million barrels from emergency stocks - the largest coordinated stock release in IEA history, by a wide margin. It cushioned the shock without erasing it. Brent still traded to $138.21 on April 7 (95 percent above the February 2026 daily average of $70.89, per FRED’s DCOILBRENTEU series), and is still hovering around $118 as of early May - 67 percent above the pre-conflict baseline.
The transmission from chokepoint to consumer price runs through a chain of distinct mechanisms. It is worth slowing down on the architecture, because that is what determines which prices move when, and by how much.
Refined products: where the consumer actually gets hit
Crude is wholesale. Diesel and jet are retail. The refined-products complex is where Hormuz turns into a credit-card statement.
Jet fuel on the US Gulf Coast (FRED’s DJFUELUSGULF) averaged $2.26 per gallon in February 2026. By March 20, it had peaked at $4.45 per gallon - 97 percent higher. As of early May it is still around $4.16, roughly 84 percent above pre-conflict. The “more than doubled” framing in trade-press reporting is not hyperbole - it is exactly what FRED’s daily series shows.
US retail gasoline (FRED GASREGW) averaged $2.91 per gallon in late February. It hit $4.45 per gallon in the week ending May 4 - a 53 percent increase, and a level not seen since the 2022 Russia-Ukraine spike.
The cleanest signal of how this hits the producer side is the Bureau of Labor Statistics’ PPI for No. 2 diesel fuel (FRED’s WPU057303). It went from an index value of 318.6 in February to 439.2 in March - a 37.8 percent month-over-month rise. That is not a price level, that is a producer price index, which means the input cost has just been delivered to every diesel-using business in the United States. They will pass it on. Some of them already have.
Why LNG and helium are the binary disruptions
Crude has bypass routes. Helium and LNG do not. That is what makes them the most structurally severe parts of this story.
The Qatar piece is the headline. Approximately 112 bcm per year of LNG transits Hormuz - roughly 95 from Qatar, 17 from the UAE - which is 19-20 percent of global LNG trade. Over 69 days, that translates to about 21.2 bcm of LNG exposure, or 235 TWh of energy content. There is no backstop. Qatar’s Ras Laffan complex sits inside the Gulf. There is no pipeline workaround. There is no second port. The IEA explicitly flagged in its March 19 update that some Qatari LNG train repairs - if any get damaged or are forced into prolonged cold-shutdown - could take up to five years to restore.
This is also why gas benchmarks diverged so sharply. European TTF rose roughly 45 percent and Asian JKM rose about 51 percent versus pre-conflict averages, both per IEA’s late April update. Meanwhile, US Henry Hub fell 26 percent (per FRED’s DHHNGSP daily series) because gas that would normally find seaborne export markets instead piled up in US pipelines and storage. The same shock produced a +50 percent move in Asia and a -26 percent move in the US. That divergence will probably persist as long as the chokepoint does.
The helium piece is less covered but arguably more strategic. Per the USGS Mineral Commodity Summaries 2024, Qatar produces approximately 35.6 percent of the world’s helium - the largest national share. The United States is second at 31.7 percent, Algeria third at 7.8 percent, and Russia fourth at 7.2 percent. Helium goes into MRI machines, semiconductor manufacturing (especially in fabs producing the most advanced nodes), rocket purging, fiber-optic manufacturing, and cryogenics. The US sourced about 40 percent of its helium imports from Qatar from 2020-2023. Spot helium prices reportedly rose 40-100 percent within weeks of the closure, with some emergency contracts reportedly clearing at 2-3x. There is no fast supply response - building helium recovery infrastructure takes years.
Beyond oil: the freight and chemistry cascade
The closure does not just price energy. It re-prices every cargo that touches a Gulf hull, every input that originates from a Gulf cracker, and every nitrogen molecule that comes from a Gulf urea or ammonia plant.
The freight piece deserves its own line. The Baltic Dirty Tanker Index (BDTI) rose 54 percent in the first week, and the Baltic Clean Tanker Index (BCTI) rose 72 percent - because tankers that would otherwise have been queuing for Hormuz instead got reassigned to longer-distance routes (Atlantic basin to Asia, US Gulf to Asia, etc.), which mechanically tightens the global tanker pool. Bunker fuel in Singapore approximately doubled. War-risk insurance on a $100 million tanker traveling routes that still touch the Gulf went from roughly $250,000 per voyage to $500,000 (a 2x premium) and as high as $1 million (a 4x premium) for the most exposed routes. Some carriers stopped quoting Gulf coverage entirely.
The fertilizer cascade is the under-reported angle. With Hormuz handling 50 percent of global seaborne sulphur and 25 percent of urea, and with cargo flows down 87 percent through May, the world is missing roughly two-thirds of a quarter’s worth of nitrogen fertilizer feedstock. That input cost will be rolled into the planting cycles of countries that depend on imported fertilizer - which is most of Africa, much of Latin America, and large parts of Southeast Asia. The food-price inflation effect from this lags the shock by roughly two crop cycles, so the effect on global food CPIs is not yet fully visible.
The petrochemicals story is structural. Wood Mackenzie’s one-month estimate of stranded production capacity (with prolonged closure) was 7 Mt of cracker feedstock, 4 Mt of gas-based chemicals (methanol, ammonia, urea), and 2 Mt of plastics. Scaled to 69 days that becomes roughly 16 / 9 / 4.6 Mt respectively - which Asian and European chemical buyers are now scrambling to source from US Gulf, Northwest European, and Korean producers. Port Houston reported chemical exports up 12 percent in March, with about 20 percent of US Gulf petrochemical capacity acting as the surge buffer.
The inflation impulse: one month was enough
This is the macro punchline, and it is the one I want readers to leave with the most clearly. One month of Hormuz closure was already enough to move every major US inflation print.
Headline CPI year-over-year accelerated to 3.32 percent in March from 3.08 percent in February (per FRED’s CPIAUCSL series). The IMF’s research on oil pass-through to CPI suggests that a 10 percent move in global oil prices feeds through to roughly 0.4 percentage points of additional domestic CPI on impact. Brent in March 2026 was averaging around 33 percent above the February 2026 baseline. That is consistent with - actually slightly larger than - the move FRED is showing. The pass-through is tracking model expectations almost exactly.
Core CPI rose to 2.67 percent (from 2.55 percent in February). PCE accelerated to 3.50 percent. Core PCE rose to 3.20 percent. The IMF non-fuel commodity index (PALLFNFINDEXM) jumped 18.7 percent month-over-month from February to March - the largest single-month move in that series in years. This is not just an oil story showing up in the CPI - it is an across-the-board commodity re-pricing showing up everywhere at once.
The IMF’s own adverse scenario for a sustained Hormuz closure projects 2026 global growth of 2.5 percent and global inflation of 5.4 percent - against a baseline of around 3.0 percent growth and 3.5-4 percent inflation. UNCTAD’s March projection was world growth of 2.6 percent, with developed economies at 1.5 percent and developing economies at 4.1 percent. Both forecasters are essentially modeling a stagflationary shock of the kind we have not seen since the early 1970s.
Recovery and what gets left behind
There is a tendency to assume these events end and everything goes back to normal. The recovery profile here looks a lot more uneven than that.
The EIA’s view is that crude flows return to pre-conflict levels only in late 2026, even if the ceasefire holds. Some Qatar LNG train repairs - if forced into prolonged cold-shutdown - could take up to five years. Geopolitical recovery is also non-trivial. China and Russia vetoed a UN Security Council resolution on the strait on April 7. Iranian Foreign Minister Abbas Araghchi said on April 17 that all commercial vessels would be allowed through under the ceasefire, but Iran’s national security council later kept the blockade pending the lifting of the US counter-blockade. Diplomatically the situation is locked.
Three things will likely persist long after the strait reopens. First, a Gulf-origin risk premium - the world has now seen the chokepoint actually close, and that is no longer a tail risk priced at zero. Second, structural demand for Westside loadings - Yanbu (Red Sea) and Fujairah (Gulf of Oman) terminals will command a sustained premium, and there will be capital expenditure to expand both. Third, a more fragmented helium market with new dual-source contracts, more on-site recycling at semiconductor fabs, and likely renewed US strategic helium reserve activity. None of these is reversible on a one-year horizon.
For markets, the ceasefire and any reopening of the strait would naturally reverse some of the moves. But the EIA’s own modeling implies oil does not return to pre-conflict prices until late 2026 at the earliest, the LNG market does not normalize on the same horizon, and the helium and fertilizer effects roll into 2027 because of crop cycles and contract structures. The “Hormuz spread” - the price difference between physically captive Gulf cargoes and Westside loadings - is going to be a tradeable structural variable for years, not weeks.
What to watch from here
The cleanest leading indicator is the daily count of vessels transiting the strait. UKMTO and Lloyd’s List both publish numbers, and if the count moves from ~5 percent of pre-conflict to even 30-40 percent, that is the signal that war-risk premiums and freight indices will start unwinding meaningfully. The next macro signal is April 2026 CPI - the data point that will tell us whether March was a one-off shock impulse or the first month of a more sustained re-acceleration. The Federal Reserve’s reaction function is tighter than people remember when commodity-driven inflation and geopolitical risk both rise at the same time, and 3.32 percent headline CPI is well above where the Fed wanted to be at this stage.
The structural takeaway is simple: the world’s most concentrated single-point-of-failure for energy actually failed. Twenty-one nautical miles of seawater can move every macro print on the global tape. Markets will eventually look through it - they always do. But the lessons that supply chains and policymakers draw from this 69-day stretch will reshape global energy infrastructure for the remainder of the decade. The Strait of Hormuz is no longer an unpriced tail risk. It is a priced structural feature.
Sources
[1] U.S. Congressional Research Service, “Iran Conflict and the Strait of Hormuz: Impacts on Oil, Gas, and Other Commodities,” Report R45281. https://www.congress.gov/crs-product/R45281
[2] House of Commons Library, “Israel/US-Iran conflict 2026: Reopening the Strait of Hormuz,” briefing CBP-10636. https://commonslibrary.parliament.uk/research-briefings/cbp-10636/ ; full PDF: https://researchbriefings.files.parliament.uk/documents/CBP-10636/CBP-10636.pdf
[3] International Energy Agency, Strait of Hormuz Factsheet 2026, plus April 2026 update.
[4] U.S. Energy Information Administration, Short-Term Energy Outlook, April 2026; STEO note on LNG infrastructure repair timelines, March 19, 2026.
[5] UN Conference on Trade and Development (UNCTAD), Global Trade Update March 2026 and April 2026.
[6] World Trade Organization / AXSMarine cargo tracker, March-May 2026.
[7] U.S. Geological Survey, Mineral Commodity Summaries 2024 (helium chapter).
[8] Lloyd’s List Intelligence reporting on the Persian Gulf Strait Authority (PGSA), May 2026.
[9] Al Jazeera, “Not ‘a litre of oil’ to pass Strait of Hormuz, expect $200 price tag: Iran,” March 11, 2026. https://www.aljazeera.com/news/2026/3/11/irans-irgc-says-not-one-litre-of-oil-will-get-through-strait-of-hormuz
[10] Discovery Alert, “Iran’s Control of the Strait of Hormuz Shipping in 2026.” https://discoveryalert.com.au/strait-hormuz-closure-iran-oil-shipping-crisis-2026/
[11] Carra Globe, “Strait of Hormuz Closure 2026: What It Means for Your Supply Chain and Shipping Routes,” March 22, 2026. https://carraglobe.com/strait-of-hormuz-closure-2026/
[12] Wood Mackenzie estimates on petrochemical feedstock disruption.
[13] ICIS / S&P Global Commodity Insights for petrochemical price and trade-flow tracking.
[14] International Monetary Fund research on oil-price pass-through to consumer price indices.
[15] Federal Reserve Economic Data (FRED), Federal Reserve Bank of St. Louis, series used in this article: DCOILBRENTEU (Brent crude), DCOILWTICO (WTI crude), DHHNGSP (Henry Hub natural gas), DJFUELUSGULF (US Gulf jet fuel), GASREGW (US regular gasoline retail, weekly), WPU057303 (PPI No. 2 diesel fuel), CPIAUCSL (Headline CPI, SA), CPILFESL (Core CPI, SA), PCEPI (PCE price index), PCEPILFE (Core PCE price index), PALLFNFINDEXM (IMF non-fuel commodity index), TWEXBGSMTH (Trade-weighted USD index, broad).
[16] U.S. Bureau of Labor Statistics (CPI / PPI underlying); U.S. Bureau of Economic Analysis (PCE underlying).
[17] Energy Institute, Statistical Review of World Energy 2024 (LNG / TWh conversion factors).
Data Driven Stocks | @stockdatamarket. Charts and schemas by the author from open-source FRED, IEA, EIA, UNCTAD, USGS, and Congressional Research Service data. This is not investment advice.