Regular gasoline in Tiffin reached as high as $4.99 per gallon Thursday, with prices at local stations ranging from $4.24 to $4.99 per gallon, according to GasBuddy data for the 44883 zip code. The lowest price found Thursday was $4.24 at the Sunoco station at 215 N. Washington St. The Murphy USA location on State Route 18 was listed at $4.26. Several stations — including the Circle K locations on Melmore Street and OH-18, and the Kroger on W. Market St. — were at $4.29. Multiple other stations, including Marathon, Speedway, Mobil, Shell, MiCKEY’S, and a Circle K on N. Sandusky St., were at $4.99.

The spike reflects a broader national and statewide surge tied directly to President Donald Trump’s ongoing war with Iran, which has effectively shut the Strait of Hormuz — a waterway that ordinarily carries roughly one-fifth of the world’s oil and natural gas supplies — since the conflict began on Feb. 28, 2026.

According to the American Automobile Association, the national average for a gallon of regular gasoline rose 27 cents in a single week to $4.30 — the highest it has been in four years, since late July 2022. The national average is $1.12 higher than it was at this time last year. Ohio’s statewide average hit $4.46 on Thursday, placing it among the 10 most expensive gasoline markets in the country, according to AAA.

Ohio drivers are paying roughly $1.39 more per gallon than they were a year ago, when the statewide average stood at $3.07, according to AAA data.

“Drivers had been seeing some minor relief at the pump, but that trend has quickly reversed as crude oil prices climb and uncertainty continues around the Strait of Hormuz,” said Nick Chabarria, a spokesperson for AAA. “Because crude oil is the main driver of gasoline prices, continued volatility in the global oil market could keep upward pressure on pump prices in the days ahead.”

Global crude prices have risen for eight straight days. U.S. West Texas Intermediate futures settled at $106.88 per barrel on Wednesday, while international benchmark Brent crude briefly surpassed $126 per barrel Thursday morning — its highest price in four years — before pulling back to close at $114.01, according to CNBC. Both contracts are up roughly 60% since the U.S. and Israeli-led war against Iran began, according to CNBC.

The war started when the United States and Israel launched airstrikes on Iran on Feb. 28. Since then, daily oil tanker traffic through the Strait of Hormuz has plunged to single digits, resulting in what the International Energy Agency has called the largest supply disruption in history, according to CNN. A ceasefire took effect April 8, but Trump has maintained a naval blockade of Iranian ports, and peace negotiations have stalled. Iran has refused to reopen the strait until the blockade is lifted.

On Wednesday, Trump told Axios that the blockade would remain in place until Iran agrees to a nuclear deal. “The blockade is somewhat more effective than the bombing,” Trump said. “They are choking like a stuffed pig, and it is going to be worse for them. They can’t have a nuclear weapon.”

Energy analysts said the market has shifted from optimism about a resolution to concern about prolonged supply disruptions. “The oil market has moved from over-optimism to the reality of the supply disruption we are seeing in the Persian Gulf,” Warren Patterson, head of commodities strategy at Dutch bank ING, said in a research note cited by CNBC. Goldman Sachs has flagged emerging demand-side risks as well, noting global oil consumption in April may be roughly 3.6 million barrels per day lower than in February.

Ohio’s gas prices can be tracked in real time through AAA’s fuel price dashboard and GasBuddy.