A process for preparing an E10 test fuel in accordance with 40 CFR 1065.710(b) includes steps of combining an aromatic pre-blend having an aromatic distribution in accordance with 40 CFR 1065.710(b), or a combination of aromatic blendstocks that if combined into a mixture would have an aromatic distribution in accordance with 40 CFR 1065.710(b), with at least one paraffinic refining blendstock, and optionally adding ethanol, butane, olefin-containing blendstocks, sulfur compounds or sulfur-containing blendstocks as needed to meet the requirements of 40 CFR 1065.710(b).