Gas prices are climbing again. See the states where it is the most and least expensive.

Filling up is getting more painful by the day.

The national average price for a gallon of regular gas rose to $4.28 on Thursday, up 6 cents in 24 hours and 13 cents over the past two days, according to AAA.

That’s $1.08 more per gallon than drivers were paying a year ago.

The price jump comes as the six-month war between the US and Iran enters another dangerous new phase for global oil supplies.

US forces have struck several Iranian oil tankers in recent days, while Iran has attacked ships and a US base in Jordan on Tuesday.

Iran-backed Houthi rebels have also set Saudi oil facilities ablaze and threatened shipping in the Red Sea.

Those attacks have further squeezed a market already strained by the near-shutdown of shipping through the Strait of Hormuz, the narrow waterway that carried roughly 20% of the world’s oil before the war.

Brent crude, the global oil benchmark, rose above $100 a barrel on Wednesday and Thursday, though it remains below its April wartime high of $126.41.

Before the escalating conflict, Brent prices had stayed below $100 a barrel since 2022.

Now, drivers are feeling it from coast to coast.

California had the country’s highest average regular-gas price on Thursday, at $5.89 a gallon, according to AAA.

Diesel, a key cost for trucking and freight, hit a record national average of $5.94 a gallon.

That, economists warn, has added to inflation beyond the pump.

Carol Spieckerman, a retail analyst, told Business Insider that the impact of higher gas prices is “far-reaching and underestimated” for the entire US economy.

She said that higher fuel costs have led to higher prices for airline tickets, groceries, and petroleum-based products — and those higher prices are harder for small businesses to weather. “If you’re a specialty retailer in a single market, higher gas prices mean fewer shopping trips and more cautious spending when customers do show up,” she said. “By comparison, retailers like Walmart that serve as convenient one-stop shops and offer delivery in many areas will benefit.

Amazon, which requires no travel at all, obviously gains ground.” For now, Americans are once again confronting a familiar reality: higher costs everywhere — from the checkout line to the gas pump.