Key Biscayne drivers are paying $1.87 more per gallon than the Miami metro average, and the 1-cent dip elsewhere didn't reach the island.

Both gas stations held at $5.79 per gallon for the week of Aug. 17, according to GasBuddy price data reported by the Key Biscayne Portal. That's the highest reported price in the Miami metropolitan area. Meanwhile, the metro average fell 1.6 cents to $3.92 per gallon.

The price hasn't moved.

A 15-gallon fill-up on Key Biscayne costs roughly $28 more than at an average Miami station, based on the $1.87 gap.

The island's price has been frozen since July 27, when it jumped 30 cents in a single week from $5.49, as we reported Aug. 11. At that time, the metro average sat at $3.93. It has since ticked down a penny while Key Biscayne stayed locked in place.

The cheapest Miami-area station was selling regular for $3.58 on Aug. 16, a $2.21-per-gallon gap below what island residents pay.

Strait of Hormuz closure, Russia strikes drive national spike

While Miami got a small break, the rest of the country moved the other direction. The national average rose 7.7 cents over the past week to $4.02 per gallon, according to GasBuddy.

Patrick De Haan, head of petroleum analysis at GasBuddy, attributed the jump to "rebounding oil prices driven by the continued closure of the Strait of Hormuz and ongoing Ukrainian attacks on Russian oil refineries" in the company's weekly price report.

The International Energy Agency's August 2026 report estimates 8.3 million barrels per day of Gulf output remain shut in. The U.S. and Iran missed their 60-day diplomatic deadline on Aug. 17, according to The Guardian, with no agreement on Iran's nuclear program.

The congressional Joint Economic Committee estimated in July that American households have paid an extra $477 on average in elevated gas costs over the six months since the Strait closure began.

No competition on the island leaves few options for relief

Key Biscayne's two stations face no local competition, and fuel must be trucked across the Rickenbacker Causeway. No official explanation for the island's premium has been provided by station operators or the village.

Drivers looking for relief can check the GasBuddy app to find the lowest-priced stations off-island before heading to the mainland. As of Aug. 16, the cheapest Miami station was at $3.58 per gallon, cutting more than $33 off a 15-gallon fill compared to the island price.