Year-Round Sale of E15

INSIGHTi

Year-Round Sale of E15

Updated June 5, 2026

E15—a fuel blend of up to 15% ethanol and 85% gasoline—generally cannot be sold during the summer

driving season (June 1–September 15) because it does not meet gasoline Reid vapor pressure (RVP)

requirements, which limit fuel volatility under the Clean Air Act (CAA). The CAA statute allows the U.S.

Environmental Protection Agency (EPA) Administrator to issue a temporary fuel waiver of these

requirements (42 U.S.C. §7545(c)(4)(C)(ii)) under certain conditions. On March 25, 2026, EPA issued the

first nationwide fuel waiver for the 2026 summer driving season. The waiver allows E15 to be sold during

the summer driving season, in part, to address extreme and unusual fuel circumstances that EPA states are

“the result of ongoing issues in the Middle East, among other events.” EPA also states its “intention to

issue new waivers effectively extending (renewing) these waivers until such time as the … circumstances

described in this action are no longer present.”

President Trump’s January 20, 2025, Executive Order (E.O.) 14156, “Declaring a National Energy

Emergency,” included a provision about the year-round sale of E15. The order (Section 2(b)) states,

Consistent with 42 U.S.C. 7545(c)(4)(C)(ii)(III), the Administrator of the Environmental Protection

Agency, after consultation with, and concurrence by, the Secretary of Energy, shall consider issuing

emergency fuel waivers to allow the year-round sale of E15 gasoline to meet any projected

temporary shortfalls in the supply of gasoline across the Nation.

The statutory provision referenced in the E.O. is the third of three factors the EPA Administrator must

consider when determining whether to issue a temporary fuel waiver: whether the waiver is “in the public

interest.” The E.O. directs the EPA Administrator to consider issuing—but does not require the

Administrator to issue—temporary fuel waivers that would allow for the year-round sale of E15. In light

of the statutory limit that requires waivers to be effective for a period of 20 calendar days or shorter, to

achieve the year-round sale of E15, the EPA Administrator would have to issue a series of consecutive

waivers as was done for prior summer driving seasons.

Congress has explored legislative options pertaining to the year-round sale of E15. In May 2026, the

House passed H.R. 1346, which, in short, would allow E15 to be sold year-round and would make

changes to the small refinery exemption component of the Renewable Fuel Standard (RFS). In the Senate,

S. 593 would also allow E-15 to be sold year-round. Some Members of Congress have requested that

“[a]ny legislative movement on E15 must be conditioned upon meaningful reforms to the Renewable Fuel

Standard (RFS).” E15 legislation was included in a short-term FY2025 spending bill introduced in the

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House in December 2024 (H.R. 10445, 118th Congress); it was not included in the FY2025 continuing

resolution package that became law (P.L. 118-158).

Clean Air Act RVP Requirements

The CAA authorizes the EPA Administrator to regulate fuels and fuel additives. The act regulates (among

other pollutants) precursors for ground-level ozone, a primary component of smog, which has been found

to negatively impact human health and welfare, among other effects. One of the requirements intended to

reduce smog is a limit on gasoline volatility because volatile organic compounds within gasoline

evaporate more readily at higher temperatures (e.g., during the summer months) and can contribute to

smog formation. RVP is a common metric of volatility—the lower the RVP, the less the substance will

evaporate. RVP requirements in Section 211(h) of the CAA—which apply to the 48 contiguous states and

the District of Columbia—generally prohibit the sale of gasoline with an RVP greater than 9.0 pounds per

square inch (psi) during the high-ozone season (i.e., the summer months). In 2012, the National

Renewable Energy Laboratory (NREL; renamed the National Laboratory of the Rockies [NLR] in

December 2025) reported that the addition of 10% ethanol to gasoline increases the RVP of the blend by

about 1.0 psi.

The CAA provides some exceptions, including a waiver—the “one-pound waiver”—stipulating that

ethanol-gasoline fuel blends containing 10% ethanol (E10) are subject to an RVP limit that is 1.0 psi

greater than what would otherwise apply given certain conditions (e.g., the 9.0 psi standard for certain

areas would subject E10 to a 10.0 psi limit). The waiver does not apply to reformulated gasoline (RFG);

there is a 7.4 psi RVP standard for RFG. EPA reports that about 30% of gasoline sold in the United States

is RFG. States may petition EPA to remove the 1-psi waiver for gasoline-ethanol blends containing 10%

ethanol (E10) (42 U.S.C. §7545(h)(5)). Some states have exercised this option. In addition, according to

EPA (for prior years), the waiver “does not apply in areas where EPA has approved a regulation into a

state implementation plan (SIP) that limits the applicability of the 1.0 psi allowance.” For the May 19,

2026, national fuel waiver, EPA reports it is “waiving the requirements in 40 C.F.R. §1090.215 that

govern volatility, and under this waiver, EPA is allowing gasoline to be distributed and sold nationwide

with an RVP of 9.0 psi (10 psi when blended with 9-15% ethanol).” EPA also reports that “[o]ther state or

local requirements or restrictions related to this matter may need to be addressed by the appropriate

authorities.” The regulations for gasoline RVP standards are available at 40 C.F.R. §1090.215.

Congressional Issues

NREL reported in 2012 that “the RVP impact of 15% ethanol is indistinguishable from that of 10%

ethanol in gasoline for all volatility seasons and base hydrocarbon vapor pressures,” and “there is no

technical reason for treating E10 differently from E15.” In general, it appears that greater substitution of

E10 with E15 may not lead to material emissions changes; however, there could be other market impacts

associated with E15. Thus, the sale of E15 year-round involves other issues that Congress may consider,

including the following:

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How much consumer demand is there for E15?

Would the additional use of ethanol for E15 reduce consumer gasoline prices?

Who pays to install E15 fueling infrastructure (e.g., blender pumps)?

Would the rural economy benefit from year-round sale of E15?

What impact might additional sales of E15 have on the RFS program?

Would the additional use of ethanol for E15 raise environmental concerns?

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What effect, if any, will California’s October 2025 authorization of the sale of E15—

while state entities review whether E15 can meet California’s clean air requirements—

have on national markets for ethanol and other transportation fuels?

Author Information

Kelsi Bracmort

Specialist in Natural Resources and Energy Policy

Disclaimer

This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff

to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of

Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of

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