Why D3, D4, D5 and D6 RINs trade at different prices

Four kinds of RIN trade under the US Renewable Fuel Standard, and between January and August 2026 their prices fell into two groups. D6 averaged US$1.71, D4 US$1.78 and D5 US$1.93, all within 22¢ of each other. The cellulosic D3 RIN averaged US$2.44, 67¢ above D4.

D4 sets the level, and D3 trades on a separate balance. A D4 RIN from biodiesel or renewable diesel counts toward three of the four standards, and its supply rose from 4.9 billion RINs in 2021 to 9.2 billion in 2024. With corn ethanol held at the E10 blend wall and cellulosic and other advanced supply small, refiners use D4 to complete both the advanced standard and the total, so D5 and D6 trade close to it. A D3 RIN also meets the cellulosic standard. Cellulosic supply fell short of that target from 2023 to 2025, and nothing caps the D3 premium unless EPA waives part of it.

The textbook ordering, with D4 above D5 and D6 almost free, held in 2011 and 2012, when D6 averaged 3¢ and 6¢. Since 2021 D4, D5 and D6 have traded close together, and only D3 has kept a wide premium. That premium narrowed from US$2.38 over D4 in 2024 to 67¢ in 2026. D3 fell 68¢ in 2025 while D4 rose 27¢, and in 2026 D4 rose another 77¢ while D3 held near US$2.44.

EPA EMTS RIN prices and traded volumes for current-year RINs, volume-weighted; EPA EMTS RIN generation; EPA cellulosic waiver credit prices; Climate Decode analysis.

Every qualifying gallon of fuel generates RINs that carry a D-code, set by the fuel, its feedstock and the production process under 40 CFR 80.1426. The D-code decides which of the four annual standards the RIN can be used for (40 CFR 80.1427), and one RIN counts toward every standard it qualifies for at once. A D4 retired by a refiner therefore meets part of its biomass-based diesel, advanced and total obligations together.

Table 1 · What each RIN type is made from and what it counts toward

EPA EMTS RIN generation by D-code and fuel category, 2025; 40 CFR 80.1426 and 80.1427; Clean Air Act section 211(o)(1), against the 2005 petroleum baseline. D7 cellulosic diesel counts toward either the cellulosic or the biomass-based diesel standard, plus advanced and total; its output is negligible, about 0.2-0.3 million RINs a year from 2021 to 2025.

The 2026 standards are 1.36 billion RINs for cellulosic biofuel, 9.07 billion for biomass-based diesel, 11.10 billion for advanced biofuel and 26.81 billion in total. The last three include part of the obligations EPA exempted for small refineries. In March 2026 EPA added 70% of the volumes exempted for 2023 and 2024, and of its projection for 2025, to the 2026 and 2027 standards. Corn ethanol supplies most of the total, but the E10 blend wall has held D6 generation between 14.3 and 14.9 billion a year since 2021.

The nesting implies that a D4 should be worth at least as much as a D5, and a D5 at least as much as a D6. A D4 can do everything a D5 can and also counts toward biomass-based diesel, while a D5 can do everything a D6 can and also counts toward advanced. D3 sits outside that chain, because it cannot meet the biomass-based diesel standard and D4 cannot meet the cellulosic one.

EPA’s averages do not always keep that order. D5 averaged less than D6 in 2023 and 2024, and D6 averaged at or above D4 in every month from April to August 2026. The figures average the prices buyers and sellers report for each transfer, and the four codes trade at different times and in very different volumes, so their averages can cross for months at a time. A buyer who can use either RIN still has no reason to pay more for the one that counts toward fewer standards.

EPA has published weekly prices for traded RINs since mid-2010. Exhibit 1 shows the monthly average for current-year RINs, the vintage a producer sells from this year’s fuel.

Exhibit 1 · Monthly RIN prices by D-code, June 2010 to August 2026

EPA EMTS weekly RIN prices for current-year RINs, all QAP types; volume-weighted from 2020, when EPA’s traded-volume data begins, and simple averages of weekly prices before that. D3 shown from August 2014, when regular trading began; months without a current-year price are bridged.

In 2011 and 2012 the biomass-based diesel standard itself was binding. D4 averaged US$1.23 and US$1.17, D5 US$0.72 and US$0.68, and D6 3¢ and 6¢, because ethanol output covered the conventional portion of the standard with RINs to spare.

From 2013 the total standard pressed against the blend wall, and D6 rose from 9¢ in January to 94¢ in August that year. It fell back to an average of 18¢ in 2019 after EPA exempted about 1.8 billion RINs of 2017 obligations and 1.4 billion of 2018’s without adding them to anyone else’s, which left ethanol in surplus.

Since 2021 the four prices have moved as two groups. D4, D5 and D6 rose and fell together, from US$1.40-1.74 in 2022 to US$0.59-0.73 in 2024 and US$1.71-1.93 so far in 2026, while D3 averaged between US$2.43 and US$3.11 a year.

Table 2 · Annual average price by RIN type, US$ per current-year RIN

EPA EMTS; method as for Exhibit 1. D3 from August 2014. Differences and ratios in the text use unrounded averages, so a few differ by a cent or a percentage point from those worked out from this table.

D6 counts only toward the total standard, so its value depends on whether ethanol can fill the conventional portion, which is the total standard less the advanced one. When it can, D6 is surplus, and in 2011 and 2012 it traded for a few cents. When it cannot, refiners have to retire D4 or D5 RINs against the total, and a D6 becomes a substitute for a D4.

Since 2022 the conventional portion has been larger than what ethanol supplies. It was 15.25 billion RINs in 2022 and 2023, including EPA’s supplemental standard, 15.00 billion in 2024 and 2025 and 15.71 billion in 2026, while D6 generation ran between 14.55 and 14.91 billion a year. D6 averaged 88% to 97% of the D4 price in each of those years, and at or above D4 in every month from April to August 2026.

Exhibit 2 · D5 and D6 prices as a share of the D4 price, 2011 to 2026

Annual averages of EPA EMTS prices for current-year RINs; 2026 covers January to August.

D6 had already climbed to 92% of D4 in 2021, before EPA set that year’s volumes in June 2022. The link holds only while ethanol is capped at the blend wall, and California adopted rules for E15 on 24 September. Wider E15 sales would let ethanol fill more of the conventional portion; until that happens at scale, a higher D4 price lifts D6 even though no extra ethanol is blended.

Only D3 and D7 RINs can meet the cellulosic standard, and D7 output is negligible. In 2025, 93% of D3 RINs came from renewable natural gas. Since January 2025 RINs on RNG have generally been generated when the gas enters a commercial pipeline, but they can be separated and used for compliance only once the gas is used as vehicle fuel. D3 supply therefore depends on how much compressed and liquefied natural gas US trucks and buses burn. EPA’s March 2026 rule for 2026 and 2027 also removed electricity as a qualifying fuel.

D3 generation more than doubled, from 0.57 billion RINs in 2021 to 1.29 billion in 2025, and still fell short of the original target in each of 2023, 2024 and 2025. EPA put the 2025 RINs available for compliance at 1.21 billion, excluding RINs retired for non-transportation use, which rose from 0.4 million in 2024 to 74.5 million in 2025. It partially waived the 2024 and 2025 targets after those years had ended.

Table 3 · The cellulosic target, D3 output and waiver credits, 2023-2027

EPA final rules for 2023-2025 (June 2023) and 2026-2027 (March 2026); EPA partial waivers of the 2024 cellulosic volume (June 2025) and the 2025 volume (March 2026); EPA EMTS RIN generation, 2026 to July because August reporting is incomplete; EPA cellulosic waiver credit prices.

That gives D3 a floor and, in waiver years, a ceiling. A D3 also counts toward the advanced and total standards, so a refiner can use it in place of an advanced RIN, and it is worth at least one, which in 2026 means a D4. The reverse does not hold, since no D4 or D5 can meet the cellulosic standard. When EPA cuts the cellulosic target under its waiver authority, it must offer cellulosic waiver credits (40 CFR 80.1456), but a credit counts only toward the cellulosic standard. A refiner that uses one in place of a D3 therefore needs a D4 as well, to cover the advanced and total standards the D3 would have met, so a D3 is worth no more than the credit plus a D4. The credit price follows a statutory formula, US$3.00 adjusted for inflation since 2008 less the wholesale gasoline price, with an inflation-adjusted floor of 25¢.

Exhibit 3 · D3 premium over D4 and the cellulosic waiver credit price, 2015 to 2026

Annual averages of EPA EMTS prices for current-year RINs, 2026 covering January to August; EPA cellulosic waiver credit prices. The 2024 credit price (hollow marker) was set in June 2025, after that year had traded. No credits were offered for 2023, and none have been for 2026.

From 2010 to 2022 EPA cut the statutory cellulosic volume by waiver every year and offered credits, and in every year from 2015 to 2022 the D3 premium averaged below the credit price. It broke through in 2024, averaging US$2.38 against a credit price of US$1.61, in a year when no waiver was in prospect. EPA had set the 2024 target in its June 2023 rule without one, refused in March 2024 to waive the 2023 target, and proposed the 2024 waiver only on 12 December 2024. The 2025 waiver was proposed in June 2025, and that year the premium averaged US$1.43 against a US$1.91 credit.

In 2026 the premium has narrowed further as D4 rose. D3 traded between US$2.30 and US$2.52 a month from February to August, while D4 rose from US$1.33 to US$2.15, and the gap fell from 98¢ to 35¢. Generation is running ahead of the target, with 853 million D3 RINs from January to July, 20% more than a year earlier and 63% of the 1.36 billion target in seven months. How many of them count depends on how much of the gas is used as vehicle fuel, and EPA has offered no waiver credits for 2026.

D5 counts toward the advanced and total standards, and a D4 counts toward both as well. In 2026 D4 is the RIN refiners use to complete the advanced standard, since D3 and D5 together supplied only about 1.6 billion of the 11.10 billion RINs required, at 2025 generation. A refiner short of advanced RINs can use either, so D5 should trade at or slightly below D4.

In practice D5 averaged more than D4 in at least eight months of each of 2021, 2022 and 2025, and in seven of the eight months to August 2026, when it averaged US$1.93, 16¢ above D4. The gap was 11¢ to 18¢ from January to March, 32¢ in April, 53¢ in June and 27¢ in July, and in August D5 averaged 5¢ below D4.

No refiner needs a D5 that a D4 could not replace, so these premiums are hard to explain from compliance alone. EPA data show 141 million current-year D5 RINs traded from January to August, 1.5% of the 9.51 billion D4 RINs, and EPA’s price table has a current-year D5 price for only 25 of the 35 weeks in that period. D5 generation was 0.28 billion RINs in 2025, 4% of D4’s 7.13 billion, and most of it was renewable naphtha and renewable diesel that does not qualify as D4. Averages built on so little trading can swing from 53¢ above D4 in June to 5¢ below it in August.

Over a longer run D5 has stayed close to D4 in both directions. Its annual average sat between 16¢ below and 16¢ above D4 from 2016 to 2026, and in 2023 and 2024 it averaged less than D6, even though it counts toward one more standard. In 2011 and 2012, when the biomass-based diesel standard was binding, D5 traded about 50¢ below D4.

On 1 January 2027 renewable diesel’s default equivalence value drops from 1.7 to 1.5 RINs a gallon, and EPA expects most producers to qualify for 1.6 by application. To hold its support per gallon, the D4 price has to rise about 6% at 1.6 and up to 13% at 1.5. EPA’s 13 October proposal would also add up to 770 million RINs to 2027 obligations. With the 2027 conventional portion at 15.70 billion RINs and ethanol near 14.9 billion, D5 and D6 should keep following D4.

The cellulosic target rises 5% to 1.43 billion RINs in 2027, while D3 generation is growing faster than that. EPA set both years’ targets expecting RNG output to exceed the gas used in vehicles, so the limit is how much RNG trucks and buses burn rather than how much is produced. A higher D4 lifts D3’s floor. Without a waiver, the premium is limited only by carried-over RINs and growth in separated supply; a partial waiver would bring credits back as a ceiling.

For Canadian buyers of US renewable diesel, D4 is the RIN that matters, because an exported gallon gives up its D4 RINs. Our analysis of EPA’s reallocation proposal sets out what a higher D4 price costs them.

Climate Decode · Advisory

Which RIN types carry your compliance cost?

We model each RFS standard, the RIN that fills it and the CFR and BC credit markets together, by year.

Sources

EPA RIN trades and price information; EPA RIN generation data; EPA cellulosic waiver credits and 2025 price calculation (EPA-420-B-26-011); EPA final Renewable Fuel Standards for 2026 and 2027, including the partial waiver of the 2025 cellulosic volume; EPA partial waiver of the 2024 cellulosic volume; EPA denial of a partial waiver of the 2023 cellulosic volume; EPA final volume standards for 2020, 2021 and 2022; EPA small refinery exemptions; 40 CFR §80.1426, §80.1427 and §80.1456; section 211(o) of the Clean Air Act; CARB E15 rules (24 September 2026); Climate Decode RFS model.

This article is analytical research provided for information only and is not investment advice.