What is the Strait of Hormuz, and Why It Is Important?

The Strait of Hormuz, which connects the Persian Gulf with the Arabian Sea via the Gulf of Oman, is a critical maritime choke point that measures 104 miles (167 km) in length, with the strait narrowing to just 20 miles (33 km) at its most constricted point. The shipping lanes, however, are much narrower, at just 2 miles (3 km) in either direction.

Generally, the flow of commercial traffic through the Strait occurs via the Traffic Separation Scheme (TSS) north of the Musandam Peninsula. However, the waters are also sufficiently deep to allow for the passage of large ships through the Inshore Traffic Zone, which is located south of the Omani island of Didimar. The depth in these waters is in excess of 650 feet, although the Omani authorities have designated this area for smaller craft under normal and peacetime conditions. The Inshore Traffic Zone was the primary passage through the Strait before 1979.

On the northern coast is Iran, while the southern coast is formed by the Musandam Peninsula, shared by Oman and the United Arab Emirates. For centuries, the strait has been an essential factor in the flow of commerce, as described in the era of Babur, who recognised the need to transport commodities such as almonds across the strait. Today, the strait carries about 20% of the world’s liquefied natural gas and a quarter of the world’s oil.

The Strait is especially important for oil transport. Every day, about 20 million barrels of crude, roughly one-fifth of global production, pass through it. Countries like Saudi Arabia, Kuwait, and other Gulf states rely on it to reach markets in Asia, Europe, and beyond. Because alternative routes are limited, any disruption can ripple through global energy markets.

Iran dominates the northern side of the strait. Throughout the years, the country has made some political and military threats by closing the Strait. Although the strait has not been closed for an extensive period, the possibility of closing the strait is always present. For example, during Iran’s 12-day conflict with Israel in 2025, analysts warned that oil prices could spike past $100 per barrel if the strait were blocked.

In recent weeks, vessels have avoided the strait after several tankers came under attack, creating what experts called an “effective halt of traffic.” Even without a formal closure, the risk alone has delayed shipments and increased global oil prices. Some LNG carriers from Qatar, including one chartered by British Gas owner Centrica, had to reroute or pause their journeys, showing just how sensitive global energy supply is to this narrow channel.

Experts note that Iran would likely only fully close the strait as a last resort. Any shutdown would hurt Iran’s own economy, halting its exports of oil and goods.

However, smaller disruptions, like jamming signals, detaining ships, or laying sea mines, have the potential for large effects on the world, increasing freight costs and hence prices.

The Strait of Hormuz is a very narrow waterway, but its significance is enormous. The Strait is a vital waterway for the world, and its control is directly linked with the region’s politics. The effects of even smaller disruptions in the region send shockwaves through the markets, which just goes to show how much the world relies on the Strait.

About 20–25% of global seaborne oil trade passes through the Strait of Hormuz each year, making it one of the world’s most important energy transport routes. Around 20 million barrels of oil per day are typically shipped through this narrow waterway, equivalent to roughly a fifth of total petroleum liquids consumed globally.

Iran controls the northern side of the Strait of Hormuz, while Oman controls the southern side. The Strait lies between Iran and the Musandam Peninsula (part of Oman and the United Arab Emirates). While Iran has significant influence because of its geography, international maritime law and foreign naval forces, such as the U.S. Fifth Fleet, also help ensure shipping passage.

A full closure would likely disrupt global energy markets, significantly tightening oil and liquefied natural gas (LNG) supplies and pushing up prices. Because so much crude oil and gas trade relies on this route with limited alternatives, even short‑term disruptions can delay shipments, increase shipping and insurance costs, and cause energy prices to rise worldwide.

The Strait of Hormuz has never been closed for an extended period in modern history. It was disrupted during past conflicts, such as the “Tanker War” in the 1980s, when Iran and Iraq attacked each other’s oil tankers, but international naval forces intervened to keep shipping lanes open. Brief closures have occurred for military exercises, but no long‑term shutdown has been sustained.