Gas Prices Today May 21, 2026: The national average gas price rose to $4.564 on Thursday (May 21, 2026), up slightly from $4.555 on Wednesday (May 20, 2026), according to the AAA Fuel Prices website, marking a modest day-over-day increase. Across the five most populous states - California, Texas, Florida, New York, and Pennsylvania - fuel prices continue to show clear regional differences. California remains the most expensive state for gasoline, while Texas consistently records some of the lowest prices. Florida sits in the middle, with prices influenced by seasonal demand shifts. Meanwhile, New York and Pennsylvania tend to stay on the higher side, driven by stronger urban demand and distribution costs. Together, these trends highlight how geography, taxation, and supply chains shape fuel prices across the country.Here are the gas price averages (per gallon) for the top 5 US states by population (Thursday, May 21, 2026):GAS Price Today in CaliforniaIn California, the current price of regular fuel is $6.143, mid-grade $6.386, premium $6.573, and diesel $7.417, according to the AAA Fuel Prices website.Gas Price Today in TexasThe AAA Fuel Prices data says that in Texas, the current price of regular fuel is $4.092, mid-grade $4.576, premium $4.943, and diesel $5.058.GAS Price Today in FloridaIn Florida, regular fuel is priced at $4.511 per gallon, mid-grade at $4.962, premium at $5.285, and diesel at $5.460.GAS Price Today in New YorkIn New York, regular fuel is priced at $4.613 per gallon, mid-grade at $5.096, premium at $5.495, and diesel at $5.936.GAS Price Today in PennsylvaniaIn Pennsylvania, regular fuel is priced at $4.645 per gallon, mid-grade at $5.067, premium at $5.458, and diesel at $5.926.