According to the AAA, gas prices in California (as of writing in November 2022, which may vary quite a bit depending on when you're reading this) stand at $5.433 for Regular. Meanwhile, Mid-Grade gas will set you back $5.630, and Premium will cost you $5.785. On the other hand, Diesel gas in California is priced at $6.264. Note, these prices shown are an average across the entire state of California, measured per gallon. California does generally have some of the costliest gas prices, alongside other states like Hawaii, Oregon, and Alaska. On the flip side, states in the South like Texas, Arkansas, Louisiana, and Georgia have the cheapest gas prices in the US.