(Garden City, UT) — Gas prices in Utah are up by one cent over the past day. Triple-A says the average price for a gallon of self-serve regular is now four-dollars and 60-cents. The most expensive average price can be found in Rich County where gas is now four-88. The least expensive average price is in Daggett County where gas is four-30. Gas is now four-58 in Salt Lake County.