How much will US Hormuz blockade hurt Iran?

The United States naval blockade of Iran began at 20:00 BST on Monday, 13 April 2026 (1400 GMT), marking a sharp escalation in efforts by the Trump administration to pressure Tehran into accepting terms aimed at ending the ongoing war that started on 28 February 2026.

The move places renewed focus on the Strait of Hormuz, a critical maritime chokepoint through which roughly 20% of global oil and gas flows. Iran has condemned the blockade as an "illegal act" amounting to "piracy".

Oil revenues under pressure

Prior to the blockade, Iran had been operating under constrained but functional export conditions. In March, crude exports were estimated at about 1.84 million barrels per day, supported by elevated global oil prices ranging between $90 and above $100 per barrel, says Al Jazeera.

That environment generated an estimated $4.97 billion in monthly revenue, a 40% increase compared with pre-war levels.

The US naval presence now threatens that flow by targeting maritime access routes and associated shipping activity. Analysts say Iran is unlikely to sustain current export volumes or continue deriving transit-related income from passing tankers.

A large share of Iran's oil exports is also exposed to Asian demand, with about 97.6% of an estimated 157.7 million barrels currently in floating storage reportedly destined for China, increasing the geopolitical sensitivity of any disruption.

Wider trade and economic exposure

Beyond crude exports, the blockade risks affecting Iran's broader trade balance, which was already under strain from sanctions and war-related disruption.

Non-oil exports — including petrochemicals, plastics and agricultural goods — are primarily shipped to China and India, and could face delays or interdiction risks under heightened maritime enforcement.

Imports are also exposed. Iran relies on external suppliers, including China, Turkey, and the United Arab Emirates, for food, machinery and electronics. Analysts say any sustained disruption could deepen shortages and pressure domestic supply chains.

Tehran's workarounds

Iran has developed several mechanisms over time to reduce exposure to maritime sanctions and enforcement, though their capacity to offset a blockade is limited.

One option is the China–Iran railway corridor, which provides an overland trade route through Central Asia. However, industry sources note that transporting large volumes of hydrocarbons by rail remains logistically constrained, and there is no confirmed evidence of oil being shifted at scale through this route.

Iran also continues to rely on so-called "dark shipping" practices, where vessels disable automatic identification systems to reduce tracking visibility. These methods are widely used for sanction evasion but carry higher risks under intensified naval surveillance.

In addition, Iran is estimated to hold around 127 million barrels of crude in floating storage, which could provide a short-term buffer if exports are further constrained.

Strategic outlook

The effectiveness of the blockade is likely to depend in part on enforcement intensity and the response of major buyers, particularly China.

Analysts say China is unlikely to fully align with restrictions that would disrupt its energy imports, complicating US objectives. There is also uncertainty over whether US naval forces will move to interdict or seize tankers carrying Iranian crude bound for major Asian markets.

The standoff leaves outcomes uncertain, with scenarios ranging from a negotiated ceasefire to further escalation involving expanded military activity in the region.