O-Formyl acetate is primarily used as an intermediate in organic synthesis, particularly in the preparation of esters and carboxylic acid derivatives. It serves as a reagent for introducing acyl groups in pharmaceutical and agrochemical manufacturing. Due to its reactivity, it is employed in acetylation and formylation reactions, enabling the modification of alcohols, amines, and other nucleophiles. Its role as a dual-functionalizing agent allows for sequential transformations in multi-step syntheses, making it valuable in the development of complex molecules. Additionally, it finds use in research laboratories for studying reaction mechanisms involving mixed anhydrides.