The gas brand with the least ethanol content is Shell. Shell gasoline has less than 10% ethanol, making it a great choice for consumers who are concerned about the effects of ethanol on their engines. In addition to having lower levels of ethanol, Shell also offers higher octane ratings and better performance overall. This makes it an ideal choice for those looking for top tier fuel quality that won't damage their car's engine or cause additional wear and tear over time. For those who want the best possible performance from their vehicles, choosing a gasoline with low levels of ethanol like Shell can provide peace of mind.