How Hormuz Closure Drove Up Plastic Costs in Asia and Why Relief Is Still Months Away

Key mechanism: The problem was not just oil — it was that no viable alternative source of naphtha existed at scale for Asia. Even when Brent crude corrected 23% from its peak in late March, polymer prices kept rising because the physical feedstock shortages persisted .

Current state of recovery after the U.S.-Iran deal

The deal:

• On 15 June 2026, the US and Iran announced a framework agreement (a memorandum of understanding) to end the war and reopen the Strait of Hormuz . A formal MoU was signed on 17 June 2026 .
• Oil prices fell more than 4% on the news, and Asian chemical-sector shares rallied sharply .

The recovery is partial and slow:

• Physical flows will take months, not days, to normalize. Analysts from Allianz Research describe the reopening as a "multi-month process, not a switch," projecting only 80% flow recovery within four months, with full normalization by end of 2026 .
• S&P Global noted that crude markets are expected to remain "tight through the summer months" even after the deal .
• Asian petrochemical prices fell following the deal, but ICIS warned that producer margins remain under pressure as demand recovery lags supply restoration .
• Economic scars remain. The New York Times and other outlets report that while relief is coming, Asia's economy and plastics supply chain are unlikely to return to normal immediately — some experts say it could take up to a year for the region to fully recover .

As of 28 June 2026 — just 11 days after the deal — a Moneycontrol report shows that food vendors across Asia were still grappling with elevated plastic costs, suggesting the price relief has not yet reached end-users .

Summary