Fuel economy standards for passenger automobiles increase at a rate of 0.90 percent per year through model year 2029. After that period, the standards increase at a rate of one percent per year through model year 2031. Non-passenger automobiles face an annual increase of 0.51 percent through model year 2029, followed by a one percent annual increase through model year 2031.

The rule removes consideration of air conditioning efficiency and off-cycle fuel consumption improvement values starting with model year 2028. It also prohibits consideration of electric vehicle fuel economy in standard setting. Credits earned in model year 2026 may be purchased and applied through model year 2031, while credits earned in model year 2027 may be purchased and used through model year 2032.

The document number for the rule is 2026-19964. The rule was filed on September 29, 2026, and has a publication date of September 30, 2026. The rule is effective 60 days after publication in the Federal Register.

Why It Matters

The elimination of inter-manufacturer credit trading in the Safer Affordable Fuel-Efficient Vehicles Rule III is part of a broader effort to reduce reliance on compliance credits and encourage steady improvement in fuel economy across vehicle fleets, as noted in the 2025 Federal Rules & Regulations document from the American Association of Motor Vehicle Administrators (AAMVA). NHTSA's 2025 rulemaking process for the Safer Affordable Fuel-Efficient Vehicles Rule III included a detailed analysis of measured fuel economy performance of gasoline- and diesel-powered passenger cars and light trucks produced for the U.S. market in model year 2022, which served as the baseline for future standards.

The 2025 version of the Safer Affordable Fuel-Efficient Vehicles Rule III proposal projected a fleetwide average of 34.5 miles per gallon (mpg) for light-duty vehicles by model year 2031, significantly below the 35 mpg target set by the Energy Independence and Security Act of 2007. The 2025 SAFE III proposal reduced the 2031 fleet-wide fuel economy standard to 34.5 mpg, a 31.5% decrease from the previous target, reflecting a significant rollback of prior standards. The 2025 Safer Affordable Fuel-Efficient Vehicles Rule III proposal faced significant opposition from environmental groups, including the Natural Resources Defense Council (NRDC), which argued that the rule would lead to increased air pollution and undermine state authority under the Clean Air Act.

Timeline

The National Highway Traffic Safety Administration issued a final rule titled Safer Affordable Fuel-Efficient Vehicles Rule III for Model Years 2022 to 2031 Passenger Cars and Light Trucks on September 29, 2026. On that same date, the rule eliminates inter-manufacturer credit trading beginning with credits earned in model year 2028. The rule recalibrates fuel economy standards for model years 2022 through 2031 on September 29, 2026.

Fuel economy standards for non-passenger automobiles increase at a rate of 0.51 percent per year through model year 2029 as of September 29, 2026. The rule was filed on September 29, 2026. The rule is effective 60 days after publication in the Federal Register as of September 29, 2026. The document number for the rule is 2026-19964 as of September 29, 2026.

What's New

The National Highway Traffic Safety Administration (NHTSA) previously issued the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule I in 2018, which set fuel economy standards for model years 2022–2025 and was later challenged in court for not meeting statutory requirements under the Energy Policy. NHTSA's 2025 rulemaking process for the Safer Affordable Fuel-Efficient Vehicles Rule III included a detailed analysis of measured fuel economy performance of gasoline- and diesel-powered passenger cars and light trucks produced for the U.S. market in model year 2022, which served as the baseline fo. The elimination of inter-manufacturer credit trading in the Safer Affordable Fuel-Efficient Vehicles Rule III is part of a broader effort to reduce reliance on compliance credits and encourage steady improvement in fuel economy across vehicle fleets, as noted in the 2025 Federal Rules & Regulations. In 2020, NHTSA finalized the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule II, which set fuel economy standards for model years 2021–2026 but was criticized for not adequately addressing climate change and failing to meet the Clean Air Act’s requirements. NHTSA's 2025 proposed rule (SAFE III) eliminated inter-manufacturer credit trading starting in 2028, a policy first introduced in the 2025 rulemaking process, which serves as a precedent for the 2026 final rule. The 2026 final rule for the Safer Affordable Fuel-Efficient Vehicles Rule III was published in the Federal Register on September 30, 2026, and became effective 60 days after publication, as stated in the official rule document.

How Sources Differ

Regarding safer affordable fuel, the National Highway Traffic Safety Administration Final Rule 2026-19964 states the National Highway Traffic Safety Administration issued a final rule titled "Safer Affordable Fuel-Efficient Vehicles Rule III for Model Years 2022 to 2031 Passenger Cars and Light Trucks." federalregister.gov states the 2026 final rule for the Safer Affordable Fuel-Efficient Vehicles Rule III was published in the Federal Register on September 30, 2026, and became effective 60 days after publication, as stated in the official rule document. Federalregister.gov states the 2025 version of the Safer Affordable Fuel-Efficient Vehicles Rule III proposal projected a fleetwide average of 34.5 miles per gallon (mpg) for light-duty vehicles by model year 2031, significantly below the 35 mpg target set by the Ene. Regarding fuel economy standards, federalregister.gov states the National Highway Traffic Safety Administration (NHTSA) previously issued the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule I in 2018, which set fuel economy standards for model years 2022–2025 and was later challenged in court fo. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for non-passenger automobiles increase at a rate of 0.51 percent per year through model year 2029. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for passenger automobiles increase at a rate of 0.90 percent per year through model year 2029. Regarding fuel economy, federalregister.gov states NHTSA's 2025 rulemaking process for the Safer Affordable Fuel-Efficient Vehicles Rule III included a detailed analysis of measured fuel economy performance of gasoline- and diesel-powered passenger cars and light trucks produced for the U.S. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for non-passenger automobiles increase at a rate of 0.51 percent per year through model year 2029. Regarding fuel economy, federalregister.gov states NHTSA's 2025 rulemaking process for the Safer Affordable Fuel-Efficient Vehicles Rule III included a detailed analysis of measured fuel economy performance of gasoline- and diesel-powered passenger cars and light trucks produced for the U.S. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for passenger automobiles increase at a rate of 0.90 percent per year through model year 2029. Regarding fuel economy standards, federalregister.gov states in 2020, NHTSA finalized the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule II, which set fuel economy standards for model years 2021–2026 but was criticized for not adequately addressing climate change and failing to meet the Clean A. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for non-passenger automobiles increase at a rate of 0.51 percent per year through model year 2029. Regarding fuel economy standards, federalregister.gov states in 2020, NHTSA finalized the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule II, which set fuel economy standards for model years 2021–2026 but was criticized for not adequately addressing climate change and failing to meet the Clean A. The National Highway Traffic Safety Administration Final Rule 2026-19964 states fuel economy standards for passenger automobiles increase at a rate of 0.90 percent per year through model year 2029.