Global oil buffers drained after absorbing 1.5 billion barrel Iran war loss

The Iran war removed roughly 1.5 billion barrels of oil from global markets between February and June, the largest daily supply loss ever recorded, according to IEA data. At its peak, the disruption reached 14 million barrels per day after Tehran throttled the Strait of Hormuz in response to U.S. and Israeli attacks on Feb. 28 — dwarfing the 5.6 million bpd lost during the 1979 Iranian Revolution and the 4.5 million bpd during the 1973 Arab oil embargo.

"This suggests traders viewed the disruption as serious but manageable, reflecting confidence in today's more resilient energy and economic systems," said John Baffes, senior economist at the World Bank.

Brent crude surged to around $126 a barrel in April — still about $20 below the 2008 record — before retreating to levels below where it traded before the conflict began. The relative price stability masked an extraordinary drawdown: countries around the world pulled roughly 1 billion barrels from strategic petroleum reserves, including a record 400 million barrel release coordinated by the IEA. China, the world's biggest oil importer, held nearly 1.4 billion barrels in storage as of December 2025 — more than the 1.2 billion barrels held by all 32 IEA members combined — and its rapid EV adoption and flexible refinery output helped ease global demand pressure.

Three factors prevented a worst-case scenario

Saudi Arabia and the UAE found alternative export routes around the Hormuz chokepoint. Asia, led by China, curtailed buying. And the coordinated reserve releases provided breathing room at a time when U.S. President Donald Trump was repeatedly stating an end to the war was imminent. The U.S. Treasury's Office of Foreign Assets Control also published General License X on June 22, a sweeping 60-day authorization allowing buyers worldwide to purchase Iranian crude with no volume cap — sending Brent down more than 3.3 percent that day.

"The market seems to have decided that this peace deal is for real," said Neil Atkinson, a former IEA official, referring to the preliminary agreement signed June 17 that halted hostilities.

The 1979 Iranian Revolution remains the largest oil crisis by cumulative supply loss — roughly 4.3 billion barrels over three years — but the current conflict has already exceeded the Arab oil embargo of 1973-74 (530-650 million barrels) and the 1991 Gulf War (roughly 516 million barrels) combined. Since the oil crisis of the 1970s, oil intensity — a measure of the role oil plays in economic activity — has fallen by more than half in most advanced economies and roughly 20 percent in emerging and developing countries, according to World Bank data.

The cost of operating without a safety net

Even with the 60-day ceasefire and Persian Gulf exports back to 75 percent of pre-war levels, the task of rebuilding global inventories is daunting. Tanker traffic data through the Strait of Hormuz tells a more pessimistic story than the price action suggests, with progress toward a final agreement moving slowly and key questions — including the fate of Iran's nuclear program — still unresolved.

At current Brent prices around $69 to $72 a barrel, replacing the reserves drawn down would likely cost more than $70 billion. The European Central Bank has already revised its 2027-2028 oil price estimate to $65-$75 a barrel, up from $63-$64 before the conflict. Morgan Stanley has set its third-quarter Brent forecast at $90 a barrel and its fourth-quarter estimate at $80, while Goldman Sachs moved its fourth-quarter 2026 Brent estimate to $80 and its 2027 average to $75.

"The markets may be underestimating the risk of further oil flow disruptions," said Saul Kavonic, head of research at MST Marquee. "Iran is likely to continue to find pretexts to stymie flows through the strait."

Every $5 increase in oil prices adds roughly $190 billion in annual costs to the global economy, based on demand of 104 million barrels per day. With buffer stocks depleted and the 60-day ceasefire clock ticking, the world is operating without a safety net in an environment still fraught with uncertainty. U.S. and Iranian officials are scheduled to meet in Doha for further talks — a breakdown could send oil prices sharply higher and quickly reverse the relief that markets have priced in.

This article is for informational purposes only and does not constitute investment advice.