High oil prices, low refinery margins

By Matthew Parish, Associate Editor

Saturday 18 April 2026

Refining is, at its essence, a business of margins rather than prices. The public imagination tends to focus on the headline number — the price of crude oil — yet for the refiner this is merely the principal cost input. Profitability resides instead in the narrow and volatile differential between input and output, known in the industry as the “crack spread”: the difference between the cost of crude oil and the sale price of refined products such as petrol, diesel and jet fuel.

It follows that when crude prices surge — as they have done in repeated episodes linked to confrontation between the United States and Iran, particularly around the Strait of Hormuz — refinery margins do not automatically rise in tandem. On the contrary, they are often compressed, truncated, or driven negative. This apparent paradox lies at the intersection of market structure, timing, physical constraints and geopolitics.

The asymmetry between crude costs and product prices

The most immediate explanation is temporal. Crude oil markets respond almost instantaneously to geopolitical shocks. When conflict threatens shipping routes or removes supply from the market, buyers bid aggressively for available barrels, and prices spike in real time.

Refined product markets however adjust more slowly. Petrol stations do not change their prices minute by minute; wholesale contracts are often fixed for periods; and in many jurisdictions governments impose explicit or implicit controls on fuel pricing. The result is a lag: refiners must purchase crude at sharply elevated prices before they can pass those costs through to consumers.

In such moments the crack spread narrows. If the input price rises faster than the output price, the margin is mechanically compressed. Academic analysis confirms that increases in crude prices are frequently associated with declining crack spreads, particularly in the short term.

Demand elasticity and political constraint

A second factor is demand sensitivity. Fuel demand, especially for transport, is not perfectly elastic. When prices rise too rapidly, consumption falls — motorists drive less, airlines reduce capacity, and industrial users seek substitutes.

Governments, acutely aware of the political consequences of high fuel prices, often intervene. This may take the form of subsidies, tax reductions, or informal pressure on retailers and refiners not to pass through the full cost increase. In Europe for example, recent reporting shows that refined fuel prices have not kept pace with surging crude costs, directly squeezing margins into negative territory.

Thus the refiner is caught between a rising cost base and a politically constrained revenue ceiling.

Physical and technological rigidity

Refining is a capital-intensive, inflexible industrial process. A refinery cannot instantly adjust its output mix or shut down without cost.

When crude prices spike, refiners might wish to reduce throughput — yet doing so risks losing market share, breaching supply contracts, or incurring high restart costs. Conversely continuing to operate means processing expensive crude into products whose prices may not justify the input cost.

The problem is particularly acute for less sophisticated refineries. Facilities lacking advanced upgrading units cannot easily convert heavy or sour crude into higher-value products, leaving them exposed when crude prices rise sharply without a commensurate rise in product demand.

Inventory effects and timing mismatches

Refining margins are also affected by inventory accounting. A refinery typically holds stocks of crude purchased at earlier prices. When crude prices surge, newly purchased barrels are expensive, but products sold may still reflect earlier, lower-cost inventories — or vice versa.

In periods of rapid price escalation, this mismatch can be severe. Refiners may find themselves selling products priced against past expectations while purchasing crude at present, elevated spot prices — a dynamic exacerbated in the current crisis, where physical crude has traded significantly above futures benchmarks.

Global dislocation: why margins diverge geographically

The recent confrontation between the United States and Iran illustrates a further complexity: margins do not move uniformly across regions.

In Europe, heavy dependence on imported crude and constrained refining capacity have led to negative margins as crude costs surged faster than product prices.

In contrast, refiners on the United States Gulf Coast — with access to domestic crude supplies and strong export markets — have experienced robust or even expanding margins.

This divergence reflects logistical realities. When global crude flows are disrupted, regions with secure supply and export flexibility can arbitrage the imbalance, selling refined products at high prices abroad. Regions without such advantages suffer margin compression.

The paradox of volatility: when margins rise instead

It must be emphasised that crude price spikes do not invariably compress margins. In some cases, refined product prices rise even faster than crude — particularly when there is a shortage of refining capacity or when specific products, such as diesel or jet fuel, are in acute demand.

Indeed earlier phases of the Iran crisis saw precisely this dynamic, with fuel markets tightening and margins expanding sharply.

The key distinction lies in whether the shock is perceived as a crude supply disruption alone, or as a broader disruption affecting refined products. When the former dominates, margins compress; when the latter prevails, margins expand.

Strategic implications in the US–Iran context

The confrontation between the United States and Iran introduces all these dynamics simultaneously. The closure or threat to the Strait of Hormuz removes a substantial share of global crude supply, pushing prices sharply upward.

At the same time, refined product markets are fragmented. Some regions experience shortages; others are constrained by policy or demand weakness. The result is volatility in crack spreads — widening in some jurisdictions, collapsing in others.

For policymakers this has profound implications. High crude prices do not necessarily translate into windfall profits for downstream industry; they may instead threaten refinery viability, particularly in regions with ageing infrastructure.

For military strategists the lesson is equally stark. Disruption of crude flows — a central feature of any conflict involving Iran — does not merely raise energy prices. It destabilises the entire downstream system, producing uneven and sometimes counterintuitive economic outcomes across allied and adversarial states alike.

Economic turbulence ahead

Refinery margins are not a simple derivative of crude prices. They are the outcome of a complex interplay between input costs, product pricing, political intervention, technological capacity and global logistics.

Yesterday’s announcement by Iran that the Strait of Hormuz would be open for business lasted barely one day before Iran declared the Strait closed again due to a failure of the US navy to cease its blockade of Iranian ports. Hence we can anticipate another immediate spike in the spot prices for crude.

When crude prices surge, as in the present cycle of confrontation between the United States and Iran, the balance of these forces often turns against refiners. Input costs rise immediately and universally; output prices rise slowly, unevenly, and sometimes not at all.

The consequence is a truncation — or even inversion — of margins. In such moments the refinery ceases to be a beneficiary of high oil prices and becomes instead one of their principal casualties.