MoRTH writes E100 and B100 into CMVR Rule 115, raises the light vehicle test limit to 3,500 kg

India now has a type approval path for cars and bikes that run on pure ethanol. The Ministry of Road Transport and Highways issued notification G.S.R. 911(E) on 23 October 2026, and it was published in the Gazette of India on 26 October 2026, signed by Additional Secretary Mahmood Ahmed. This is a filing, not a launch. Nothing about it puts a new model in a showroom.

The change itself is small on paper. In Rule 115 of the Central Motor Vehicles Rules, 1989, which carries India's mass emission standards and the fuels used to test against them, the references to E85 in sub-rules (18), (19), (20) and (22) now read "E85 or E100". An explanatory note has been inserted under sub-rule (19) saying that E85 or E100 shall be used in vehicles designed by the original equipment manufacturer as flex fuel vehicles. The petrol entries have been formalised as E10 and E20. On the diesel side, the B10 biodiesel entry becomes B100. Under Rule 115E, the annexure reference moves from S to SA for E100 vehicles.

MoRTH did not spring this. The draft went out as G.S.R. 313(E) on 27 April 2026 with the usual 30-day comment window, so the industry has had six months to plan test programmes around it.

The 3,500 kg line matters as much as the fuel

Buried in the same notification is a change that has nothing to do with ethanol. The gross vehicle weight threshold in the heading of the relevant emission table has been raised from 3,000 kg to 3,500 kg. In practice that widens the band of vehicles tested on a chassis dynamometer drive cycle instead of being pushed to heavy duty engine dynamometer testing. For makers of heavy electrified SUVs, large vans and small commercial vehicles that sit just above 3,000 kg, that is a cheaper and faster certification route at ARAI or ICAT.

What it means for Indian buyers

Very little, immediately. A senior MoRTH official told PTI that fuel beyond E20 and up to E100 is intended only for vehicles designed and certified to use it. E20 has been the standard petrol at pumps since April 2026, and E85 has been promoted at a handful of IOCL outlets only since the middle of this year. There is no retail E100 network, so an E100 certificate is of no use to a private buyer yet.

What it does unlock is the gap between what makers claim and what they can certify. Maruti Suzuki began deliveries of the Wagon R Bioflex on 17 June 2026 at ₹7.24 lakh ex-showroom, with a 91hp, 114Nm 1.2-litre naturally aspirated petrol engine, and Autocar India reported it as capable of running on blends from E20 to E100. Until 23 October, the emission test provisions in Rule 115 stopped at E85. Now a maker can take a flex fuel car or two-wheeler through homologation on E100 itself rather than certifying to a lower blend and advertising a higher one.

Watch the Vahan maker-model homologation entries over the next few quarters for flex fuel variant codes from Maruti Suzuki, Toyota and the two-wheeler makers. Those filings, not press releases, will show who is actually testing to E100. B100 is a thinner story: most engines in India are validated only to about B20 without re-engineering, and feedstock supply remains the bottleneck.

Treat all of this as certified, not launched. The rule is in force from the date of publication. A model is news when a filing or an official announcement names it.

Sources

• MoRTH CMVR Amendment Formalises E100 and B100 Homologation Norms, Autocar Professional
• India formally amends motor vehicle rules to add E100 alongside E85 for flex fuel vehicles, ChiniMandi
• Will E100 be made main option at pumps after changes to Central Motor Vehicles Rules? Centre clarifies, The Week
• Maruti Wagon R flex fuel now offered to private buyers as deliveries begin, Autocar India