IEA Sees Global Oil Supply Falling 5.7m b/d in 2026 as Gulf Crisis Drains Inventories

The International Energy Agency has sharply downgraded its 2026 oil outlook, forecasting global oil supply will fall by 5.7 million barrels per day as disrupted Gulf flows, attacks on energy infrastructure and refinery outages drain inventories faster than weakening demand can rebalance the market.

The latest IEA Oil Market Report marks another major deterioration in the global oil outlook.

Global production fell by roughly 1.6 million barrels per day month-on-month to 100.1 million b/d in August, with more than 10 million b/d of Gulf output still shut in amid persistent security and export constraints.

The IEA now expects world supply to average 100.7 million b/d for 2026, representing a decline of 5.7 million b/d compared with last year.

Only one month earlier, the agency had projected a decline of roughly 4.3 million b/d.

IEA cuts global oil supply 2026 forecast to a 5.7m b/d decline

The IEA’s September report represents a significant downgrade from its August outlook.

In August, the agency expected global oil supply to decline by approximately 4.3 million b/d in 2026.

It now expects a fall of 5.7 million b/d.

The direction of travel is therefore clear: every failure to restore normal Gulf exports is forcing forecasters to push the expected recovery further into the future.

The IEA now expects a meaningful rebound of roughly 8 million b/d in 2027, assuming Gulf production and trade routes recover.

Why is global oil supply falling in 2026?

The supply decline is not the result of one producer simply choosing to cut output.

It reflects several disruptions occurring simultaneously.

• Severely constrained Gulf oil exports.
• Reduced traffic through the Strait of Hormuz.
• Attacks on tankers and energy infrastructure.
• Disruption around the Bab el-Mandeb and Red Sea.
• Saudi production and export losses.
• Russian refinery and production disruption.
• Reduced volumes of oil moving by sea.

The IEA estimates more than 10 million b/d of Gulf production remained shut in during August.

At the same time, the volume of oil physically moving on water declined by approximately 65 million barrels during the month as tanker traffic out of the Middle East came under renewed pressure.

Saudi crude supply falls to 6m b/d — lowest in more than three decades

Saudi Arabia is one of the most striking parts of the new forecast.

The IEA estimates Saudi crude supply fell by 2.3 million b/d in August to just 6 million b/d.

That is the lowest level recorded by the agency in more than three decades.

Reuters reported that the IEA linked the decline to attacks on Saudi energy facilities and disruption to shipping routes.

Saudi crude loadings — including Red Sea exports and estimated “dark” shipping movements — fell by roughly 1.1 million b/d month-on-month to 3.5 million b/d.

Saudi oil inventories were also estimated to have declined by around 400,000 b/d during the period.

The IEA has consequently reduced its forecast for average Saudi crude supply in 2026 by another 885,000 b/d to 7.6 million b/d.

The latest pressure comes as Saudi Arabia has also temporarily shut its strategic East-West Pipeline following attacks.

Read Tide Signal’s full analysis: Saudi East-West Pipeline Shut as Bab el-Mandeb Shipping Risk Rises.

Global oil inventories are becoming the market’s shock absorber

The supply shortfall has not yet translated into an equivalent shortage of fuel for consumers because inventories are absorbing part of the shock.

But those buffers are shrinking rapidly.

The IEA estimates global observed oil inventories fell by another 95 million barrels in August.

Since February, cumulative observed stock draws have reached approximately 507 million barrels.

Reuters calculated the August draw at an annualised pace equivalent to around 3.1 million b/d.

The implication becomes more serious the longer Gulf exports remain constrained.

Inventories cannot permanently replace missing production.

The Strait of Hormuz remains central to the global oil supply problem

The IEA’s forecast cannot be separated from the continuing disruption around the Strait of Hormuz.

Before the regional conflict, Hormuz handled one of the largest concentrations of oil and LNG trade anywhere in the world.

Traffic has since fallen dramatically.

Tide Signal’s continuing Strait of Hormuz shipping analysis has tracked the collapse in visible vessel traffic and the consequences for tanker availability, insurance and sanctions risk.

The U.S. Energy Information Administration’s September outlook similarly expects Middle East exports to remain constrained through the end of 2026.

The EIA does not expect regional production and trade flows to return close to normal before approximately the second quarter of 2027.

See the latest EIA Short-Term Energy Outlook.

What falling oil supply means for tanker markets

A fall in global production does not automatically mean weaker tanker rates.

During a geopolitical supply shock, the opposite can happen.

Why?

Because the tanker market is driven not only by total cargo volume, but also by:

• where replacement barrels originate;
• how far they must travel;
• which routes remain acceptable;
• whether vessels are willing to enter high-risk regions;
• insurance availability;
• sanctions and compliance;
• tonnage positioning;
• voyage duration.

The effect is already visible.

Gulf of Oman-to-China VLCC freight recently reached around WS450, roughly $11.50 per barrel.

For the mechanics behind tanker freight quotations, see Tide Signal Academy’s Worldscale in Shipping guide.

Earlier in the disruption, one Iraqi crude fixture reportedly reached as much as $25 million for a single VLCC voyage.

The real tanker shortage is a shortage of workable ships

During a security crisis, headline fleet size can become misleading.

A tanker can exist physically but still be unavailable for a cargo because it is:

• outside the required loading window;
• not approved by the charterer;
• restricted by insurance;
• unwilling to enter the region;
• affected by sanctions;
• committed elsewhere;
• priced beyond the charterer’s economics.

This is the same mechanism behind the extraordinary Gulf freight levels seen in recent weeks.

Tide Signal’s War Risk Premiums in Shipping explains how security exposure can affect freight, charterparty terms and the real voyage margin before a ship even reaches the loading port.

The refining system is also under extreme pressure

Crude availability is only one half of the market.

The second half is refining.

IEA data show global refinery throughputs reached approximately 81.4 million b/d in August.

That was around 4.2 million b/d lower than a year earlier.

The agency expects global refinery runs to decline by roughly 2.6 million b/d in 2026 to 81.5 million b/d.

Outages and disruptions are concentrated across:

• the Middle East;
• Russia;
• Asian crude-importing economies.

That helps explain why refined products have become even tighter than crude.

Diesel is one of the clearest warning signals

The IEA estimates Gulf net exports of diesel and gasoil averaged just 390,000 b/d in August.

That is only slightly more than one quarter of pre-war levels.

When the Gulf and Russia are combined, diesel/gasoil exports were approximately 1.6 million b/d below February levels.

Before the disruption, those regions together accounted for almost 45% of global seaborne diesel/gasoil trade.

IEA sees world oil demand falling by 2.5m b/d in 2026

High fuel prices are also damaging consumption.

The IEA now expects global oil demand to decline by 2.5 million b/d in 2026.

Its previous forecast was for a decline of around 1.6 million b/d.

The agency expects the largest weakness in:

• middle distillates;
• petrochemical feedstocks;
• Asian consumption.

But lower demand has not been enough to rebalance the physical market because supply is falling even faster.

IEA and OPEC are sending very different demand signals

One of the most striking features of the current market is the disagreement between the major forecasters.

Both organisations, however, expect a material recovery in consumption in 2027.

The IEA expects demand to rebound by approximately 2.6 million b/d, while OPEC expects growth of around 2.36 million b/d.

That divergence makes demand data one of the most important variables to watch through the final quarter.

The EIA also expects the Gulf recovery to extend into 2027

The IEA is not alone in expecting a slow normalisation.

The U.S. Energy Information Administration’s September Short-Term Energy Outlook assumes constrained Middle East exports will persist through the end of 2026.

The EIA estimates crude-production shut-ins averaged about 6.7 million b/d in August and projects significant disruptions to continue through the fourth quarter.

It expects producers to increasingly use:

• pipeline bypasses;
• alternative export routes;
• ship-to-ship transfers;
• new infrastructure.

But even under those assumptions, the EIA does not expect most regional production and trade patterns to recover to pre-conflict averages before 2027.

Oil prices and freight are reflecting the physical squeeze

North Sea Dated crude averaged around $91 per barrel in August, according to the IEA, before reaching approximately $113.48 per barrel on 9 September.

Reuters reported Brent settling at $104.61 on 11 September, while WTI closed at approximately $100.05.

The crude market is therefore pricing several risks at once:

• lower physical production;
• declining inventories;
• shipping disruption;
• war-risk exposure;
• refining outages;
• replacement crude demand;
• uncertain diplomatic progress.

For tanker charterers, the freight bill adds another layer.

When vessels demand extraordinary premiums to enter the region, the delivered cost of a barrel can rise much faster than the crude benchmark itself.

Why shrinking inventories matter more with every month that passes

An inventory draw is not necessarily a crisis.

Stocks are supposed to act as a buffer during temporary supply disruption.

The problem arises when the disruption persists.

The longer Gulf exports remain constrained, the less comfortable the buffer becomes.

That increases the importance of every additional refinery outage, pipeline incident or tanker attack.

What owners, charterers and traders should watch next

Global oil supply 2026: frequently asked questions

How much does the IEA expect global oil supply to fall in 2026?

The International Energy Agency expects global oil supply to decline by approximately 5.7 million barrels per day in 2026 compared with 2025.

What will global oil supply average in 2026?

The IEA forecasts total world oil supply at approximately 100.7 million barrels per day.

Why is global oil supply falling?

The decline reflects major Gulf production shut-ins, constrained Strait of Hormuz exports, attacks on shipping and energy infrastructure, Saudi output losses and disruption to Russian production and refining.

How much oil is Saudi Arabia supplying?

The IEA estimates Saudi crude supply fell to approximately 6 million b/d in August 2026, the lowest level in more than three decades.

How much did Saudi supply fall in August?

The IEA estimates a month-on-month decline of approximately 2.3 million b/d.

Are global oil inventories falling?

Yes. The IEA estimates observed global inventories declined by another 95 million barrels in August and by around 507 million barrels cumulatively since February.

Is global oil demand also falling?

Yes. The IEA expects world oil demand to decline by approximately 2.5 million b/d in 2026, partly because high fuel prices are reducing consumption.

Why can tanker rates rise when oil supply falls?

Replacement crude may have to travel longer distances, while war risk, insurance restrictions and owner reluctance can reduce the number of vessels commercially available for high-risk trades. That can increase tonne-mile demand and tighten effective tanker supply.

When does the IEA expect Gulf oil supply to recover?

The agency has pushed a fuller recovery into 2027 because normal Gulf production and export flows have taken longer to restore than previously expected.

What does the EIA expect?

The U.S. EIA also expects constraints on Middle East oil exports to continue through late 2026 and sees a broader return toward pre-conflict production and trade flows extending into 2027.

Reporting status: Updated 12 September 2026. Supply, demand, inventory, refinery and production figures are based primarily on the IEA September 2026 Oil Market Report, supplemented by current EIA and Reuters reporting. Oil-market forecasts remain subject to revision as Gulf shipping, production and regional security conditions change.