Iranian drivers lined up overnight at gas stations as the government raised the price of gasoline by up to 75 percent at midnight.
Despite the increases, gasoline remains heavily subsidized and the retail price is among the cheapest in the world.
As of midnight, gasoline in Iran costs between $0.28 and $0.39 per liter.
Nonetheless, with unemployment and underemployment high and inflation at about 35 percent, the price increase could trigger unrest. In 2007, the government sparked rioting by introducing rationing of gasoline.
Iran has suffered from broad international sanctions over Tehran's disputed nuclear program. President Hassan Rohani has been negotiating intensely with the international community in a bid to get sanctions eased.
Based on reporting by the BBC, Reuters, and AP