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EXPLAINER · FEDERAL RULES

What is the federal Reformulated Gasoline program?

The federal Reformulated Gasoline (RFG) program, run by the EPA, requires a cleaner-burning gasoline blend in U.S. metropolitan areas with serious ozone-pollution problems. The program covers roughly 30 percent of U.S. gasoline sales and adds about 7 cents per gallon to the retail price in covered areas.

What it is

The federal Reformulated Gasoline program was created by the 1990 Clean Air Act Amendments to reduce smog-forming emissions in U.S. metropolitan areas with the worst ozone problems. Areas classified as "severe" or "extreme" ozone non-attainment must use RFG-blend gasoline year-round. Other ozone non-attainment areas may opt into the program voluntarily.

RFG-blend gasoline has stricter specifications than conventional federal-grade gasoline on:

What it costs drivers

RFG retail premium
~7 ¢/gal
Above conventional gasoline
Share of U.S. market
~30%
By gallons sold
Number of states affected
~17
Plus the District of Columbia

The RFG retail premium is one of the smaller policy factors in our analysis at about 7 cents per gallon. It is statistically significant but modest compared to the larger drivers (state taxes, carbon programs, West Coast supply isolation). The cost is paid by drivers in covered metro areas — Chicago, New York, Philadelphia, Boston, Houston, Dallas-Fort Worth, Hartford, Louisville, Milwaukee, St. Louis, Washington D.C., Baltimore, Sacramento, Los Angeles, San Francisco Bay Area, Norfolk-Virginia Beach, and others. Drivers in the same state who live outside the covered area pay the conventional-gasoline price.

Which metros are covered

Metropolitan areaState
Los AngelesCA
San Francisco Bay AreaCA
SacramentoCA
San DiegoCA
ChicagoIL
MilwaukeeWI
St. LouisMO and IL
LouisvilleKY (and Southern Indiana)
CincinnatiOH
Houston-Galveston-BrazoriaTX
Dallas-Fort WorthTX
AtlantaGA
Washington D.C. metroDC, MD, VA
BaltimoreMD
PhiladelphiaPA, NJ, DE
New York City metroNY, NJ, CT
BostonMA, NH, RI
HartfordCT
Norfolk-Virginia BeachVA

How it differs from California's CARB blend

The federal RFG program is administered by the EPA and applies in metros across the country. California's CARB blend is administered by the California Air Resources Board and applies only in California, with stricter specifications than federal RFG. Within California, refineries produce a single CARB-spec blend that also satisfies federal RFG requirements where the federal program applies (Los Angeles, the Bay Area, Sacramento). Outside California, the federal RFG areas use a federal RFG blend that does not meet CARB specifications.

History

The federal RFG program took effect on January 1, 1995, as required by the Clean Air Act Amendments of 1990. The initial program covered nine metropolitan areas with the worst ozone problems. The program expanded in 2001 with stricter sulfur limits and reformulation requirements. In 2006, the program shifted from MTBE (methyl tertiary butyl ether) to ethanol as the required oxygenate after MTBE was implicated in groundwater contamination.

The EPA periodically reviews the RFG program's coverage. Some metropolitan areas have been redesignated from non-attainment to attainment status since the program began, but RFG requirements typically remain in place under "anti-backsliding" provisions to prevent air-quality regression.

The debate

Supporters of the RFG program argue it has measurably improved air quality in covered areas and reduced ozone-related health impacts. EPA estimates suggest the program reduced volatile organic compound emissions by 17 percent and benzene emissions by 40 percent in covered areas.

Critics, including refiners and some consumer groups, argue the program raises retail prices in covered areas, complicates refinery operations (because refineries must produce multiple gasoline grades), and that modern vehicle emission controls have reduced the marginal benefit of reformulated fuel. The Institute for Energy Research has criticized expansions of EPA refinery regulations on the grounds they could trigger additional refinery closures.

FAQ

Why is summer gasoline different from winter gasoline?

Federal RFG and many state programs require lower-volatility gasoline in summer months to reduce evaporative emissions in hot weather. This is sometimes called "summer blend." Summer-blend gasoline is more expensive to produce, which is one reason gas prices typically rise in late spring and fall in early autumn.

Can a metro opt out of the RFG program?

In principle yes, if the metro has been redesignated to ozone attainment status and the state requests removal. In practice, removal is rare due to anti-backsliding provisions. Several metros have requested opt-outs over the years; most have been denied or remain pending.

Is RFG required year-round or just in summer?

Federal RFG is required year-round in covered metros, though the summer specifications are stricter than winter specifications. Some areas use a federal "low-RVP" (Reid Vapor Pressure) requirement only in summer, which is a less stringent version of RFG.

Sources

  1. U.S. Environmental Protection Agency, Reformulated Gasoline Program, epa.gov/gasoline-standards/reformulated-gasoline.
  2. Clean Air Act Amendments of 1990, Section 211(k).
  3. Institute for Energy Research, "EPA's Proposed Refinery Regulation Could Shutter More U.S. Refineries and Significantly Increase Gasoline Costs," October 27, 2023.