Inside this article

Inside the article

Brent and WTI usually move in the same direction, but this week the gap between them became one of the most useful signals in oil. Reuters reported a September 25 snapshot with Brent near $105.11 and WTI near $92.61, putting the spread around $12.50 a barrel, its widest since May. At that point Brent was still up roughly 1.7% for the week while WTI was down about 7.2%.

This does not mean one benchmark is right and the other is wrong. They are pricing different physical risks.

DriverBrentWTIWhy it matters
Gulf/Hormuz riskdirectindirectsupports a global risk premium
US supply and inventoriessecondarydirectmatters more for the US benchmark
Possible US diesel export banindirectpotential pressurecould weaken incentives to run domestic crude
Saudi geopolitical riskhigh sensitivitylowersupports Brent relative value

Why Brent keeps a larger premium

Brent is more exposed to internationally traded barrels. Attacks around Saudi infrastructure, uncertainty around the Strait of Hormuz and fragile shipping routes can add a risk premium to global crude even when diplomacy improves. That premium is not removed by headlines alone; markets need evidence that physical flows are normalising.

Why WTI is weaker

The US side has a different balance. Reuters linked part of the wider discount in WTI to Washington's discussion of a possible diesel export ban. If more diesel were trapped in the domestic market, refiners could have less incentive to maximise crude runs. That can weaken marginal demand for US crude and deepen WTI's discount to Brent.

Recent EIA data adds another layer: US commercial crude inventories increased and stocks at Cushing, the WTI delivery hub, also rose. That is not an automatic bearish signal, but it makes the US physical picture less tight than the global one.

A spread is a diagnostic, not a trade signal

A wide Brent-WTI spread is not an automatic instruction to buy Brent or sell WTI. It can narrow quickly if geopolitical risk falls, US fuel policy changes or inventories tighten. For CFD traders, the useful interpretation is that the spread measures divergence between two different physical balances.

For the refining side of the same energy complex, see our analysis of record Asian diesel margins.

What to watch next

Three checks matter more than a price target: actual progress in US-Iran talks and Gulf flows; concrete policy rather than rumours on US diesel exports; and the next EIA readings for Cushing, refinery utilisation and refined products.

As long as those drivers remain split, Brent-WTI may tell traders more than the headline daily move in crude.

Sources

Reuters, 25 September 2026: https://www.reuters.com/business/energy/ (reporting on the Brent-WTI spread, US diesel-export-ban discussion and Gulf supply risk)
Reuters/LSEG reporting republished by MarketScreener, 25 September 2026: https://www.marketscreener.com/news/talk-of-us-export-ban-on-diesel-deepens-us-crude-futures-discount-to-global-benchmark-ce785adfdc89f02c
Reuters/LSEG reporting republished by MarketScreener, 25 September 2026: https://www.marketscreener.com/news/oil-prices-fall-as-markets-look-to-iran-truce-but-remain-wary-of-attacks-on-oil-facilities-ce785adfdb8cf525