Iran’s biggest oil export terminal is going dark. Satellite snapshots show the jetties at Kharg Island sitting empty for days on end, a stunning sign that the US naval blockade is finally choking the lifeblood of Tehran’s economy. Storage tanks are swelling, tankers are stranded, and analysts warn the country could soon be forced to shut wells.

Empty Berths Tell a Bigger Story

The oil jetties at Iran’s Kharg Island were once again empty on Tuesday, curbing the nation’s ability to export crude, satellite images collected by Bloomberg show. It means that for a fourth consecutive period when satellites have captured what’s going on at the country’s main oil facility, no tankers have been spotted. It’s by far the longest stretch since the US and Israel launched the war that the jetties have been devoid of tankers.

There were no ocean-going oil tankers observed at Kharg Island on May 8, 9 or 11, European satellite imagery compiled by Bloomberg shows. While there have been individual days when the jetties have been empty since the conflict began, this is by far the longest stretch when no tankers have been spotted.

There are satellite images of the Kharg Island jetties on 33 out of the 73 days since the US and Israel launched their attacks on Feb. 28. Only two of the earlier images show no tankers moored, one in mid-April and one in early March. That pattern has now broken.

empty Kharg Island oil jetties Iran crude export blockade

Why Kharg Island Matters So Much

Kharg is not just another port. It is the heart of Iran’s oil trade.

Iran is the third largest oil producer in the Organization of the Petroleum Exporting Countries (OPEC) after Saudi Arabia and Iraq and exports 90 percent of its crude oil via Kharg Island in the Gulf for shipping through the Strait of Hormuz. Kharg’s deepwater location allows VLCC loading, something much of Iran’s coast cannot do.

Over the last 12 months, around 94% of Iran’s crude exports originated from Kharg. Of the country’s roughly 587 Mbbl (1.61 Mbd) of crude exports nationwide, around 553 Mbbl (1.52 Mbd) passed through Kharg alone.

The terminal also stores a huge buffer of barrels. Kpler data shows the NIOC Kharg Island terminal has total storage capacity of around 31 Mbbl. As of 7 March, inventories stood at nearly 18 Mbbl, or about 58% of capacity, giving Iran operational buffer it can use to smooth exports when production or logistics are disrupted. That cushion is now shrinking fast.

The US Blockade Is Squeezing the Flow

Washington’s pressure campaign began with bombs and ended with warships parked across Iran’s exit routes.

On 13 March 2026, the United States Air Force conducted a large bombing raid on Kharg Island, a key oil export hub off the Persian Gulf coast of Iran. The strikes targeted more than 90 Iranian military sites while deliberately avoiding damage to oil and gas infrastructure. A month later, the noose tightened at sea.

The US naval blockade of Iranian ports and the Strait of Hormuz, in place since April 13, has raised concerns that Iran could run out of crude oil storage capacity and be forced to curb production. The US is restricting the flow of ships into and out of Iranian ports, something that will sooner or later mean the country runs out of tankers that can load.

The financial sting is sharp. US Treasury Secretary Scott Bessent wrote on X this week that Kharg Island is “soon nearing capacity.” It’s a reality he said would cost Iran $170 million per day in lost revenue and force it to the negotiating table.

Storage Tanks Filling, Floating Storage Building

With no place for the oil to go, Iran is piling barrels into every available vessel and tank.

• Kayrros estimates that Iran has about 22 million barrels of on-land storage capacity remaining, which would take about six weeks to fill up based on the 500,000 barrel-a-day rate of increase Iranian inventories have seen since the war began.
• If normal export volumes were fully diverted into storage tanks then they would fill up in just under two weeks, it said.
• The number of very large crude carriers has risen from just three on April 11, two days before Washington imposed its blockade, to at least 18 tankers of various sizes by May 11.
• Stockpiles at the Iranian port of Jask, which is outside of the Strait of Hormuz but still within the US blockade, increased by 1.6 million barrels a day last week, the most of any facility in the country.

With tanker loadings seemingly paused, storage tanks on Kharg Island appear to be filling up, analysis of the satellite images shows. The tanks have floating roofs that rise as they fill, reducing the distance between the top of the tank wall and the roof. This shrinks the shadows cast by the side of the reservoir onto its top, so a comparison of photos taken at the same time on different days reveals how the volume of oil inside has changed.

“It looks like there’s been a significant slowdown in production. There is stress in the system.” Antoine Halff, co-founder and chief analyst at Kayrros

An Oil Spill and a Bigger Crisis

Adding to the chaos, a large slick appeared in the same waters last week. The oil, visible in images captured by the Copernicus Sentinel-1, Sentinel-2 and Sentinel-3 satellites between May 6 and 8, appeared as a grey-and-white slick west of Kharg Island, which handles the bulk of Iran’s crude oil exports in the Gulf.

Iranian Vice President Shina Ansari said the slick was caused by a tanker from another country dumping ballast water contaminated by oily substances, rather than a leak from Iranian pipelines or oil facilities, state media reported. Independent analysts are not so sure. The New York Times reported a 3,000 barrel leak at the facility based on a May 6 image, something that could have affected loadings.

What This Means for Oil Prices and Global Buyers

Crude markets are already feeling the pressure. Iran has begun trimming output to stay ahead of the storage crunch.

Tehran is proactively reducing crude output in a move to stay ahead of capacity limits rather than waiting for tanks to fill completely, according to the senior official, who asked not to be identified because the information is sensitive. And engineers have learned how to idle wells without lasting damage and restart them quickly, officials say, after years of sanctions and shutdowns pushed the country’s oil industry through cycles of disruption.

The biggest losers could be Iran’s Asian buyers. Kharg Island, where US forces said they had destroyed military targets earlier in the war, is the hub for 90% of Iran’s oil exports, much of which is bound for China. Chinese refiners that depend on discounted Iranian barrels are now scrambling for alternatives.

Iran is hunting for backdoors too. Another alternative is overland transportation to countries like Turkey, Pakistan, Afghanistan and Uzbekistan, Hosseini said, adding that capacity would be 250,000 to 300,000 barrels per day. That is a small fraction of what Kharg moves on a normal day.

Meanwhile, ripple effects are reshaping global shipping lanes. The Panama Canal has nearly reached capacity limits with hundreds of vessels queueing on both sides, due to an overwhelming surge in crude oil and petroleum product transits in April, driven by Asian buyers rerouting from Strait of Hormuz disruptions towards US suppliers, fueling bidding wars for priority transit slots resulting in record bids as reported on May 12, 2026.

For now, the silence on Kharg’s piers speaks louder than any official statement from Tehran or Washington. Each empty satellite frame is another sign that the standoff is reaching a breaking point, with millions of barrels backed up, thousands of workers in limbo, and an economy built on oil running out of places to put it. The next few weeks will reveal whether Iran finds a way to push barrels out or finally turns off the taps. Share your thoughts in the comments below and let us know how you think this Gulf showdown will end.