Transportation sector CO₂ emissions in the U.S. 1980-2021, by state
Texas and California are by far the biggest contributors to transportation-related emissions in the United States. Transportation in Texas and California produced 215 and 179 million metric tons of carbon dioxide (MtCO₂) in 2021, respectively, with emissions in both states rebounding from the COVID-19-related reductions in 2020. Combined, these two states account for more than 20 percent of total U.S. transportation emissions.
Transportation emissions have historically been highest in California, but in 2013 emissions in Texas surpassed them for the first time. This was due to rising emissions in Texas, as well as reductions in transportation emissions in California between 2007 and 2013. California has set a goal to ban the sale of new gas-fueled cars by 2035.