A microwave-based method for the acylation of alcohols, phenols, and thiols has been developed without the need of a catalyst or base additives. The reaction is far more rapid than previously reported acylation methods, tolerates a wide variety of functional groups, and provides easy isolation of products in excellent yields without the need for chromatography. Most products can be isolated directly via evaporation under reduced pressure or by pouring the reaction mixture into water and filtering.