The identification of sustainable fuels that exhibit optimal physico-chemical properties, can be synthesized from widely available feed-stocks, enable cost-effective large-scale production, and integrate seamlessly with existing infrastructure is essential for reducing global carbon emissions. Given their high energy density, efficient handling, and versatility across applications, renewable liquid fuels remain a critical component of even the most ambitious energy transition scenarios. Lactones, cyclic esters derived from the esterification of hydroxycarboxylic acids, feature a ring structure incorporating both a carbonyl group (C=O) and an ether oxygen (O). Variations in ring size and carbon chain length significantly influence their physicochemical properties, which in turn affect their performance in internal combustion engines. According to predictive models based on artificial neural networks, valerolactone, hexalactone, and heptalactone isomers show promise as fuels in spark-ignition engines due to their high octane (RON and MON) values. In this work, a novel blending study of three lactones was performed to understand miscibility with iso-octane and certification gasoline and blending limitations. A blending limitation for one of the lactones was discovered and a single blend fraction of 30% lactone balanced with certification gas was tested in a spark ignition engine for the three lactones. An equivalence ratio sweep was performed for each fueling blend tested and no reduction in IMEPn and net fuel conversion efficiency was observed by displacing certification gasoline with renewable fuel.