Abstract Thioesterification can be realized via an odorless, one‐pot reaction through the in situ generation of S ‐alkylisothiouronium salts from organic halides and thiourea in aqueous Triton X‐100 (TX100) micelles. The protocol is free of foul‐smell thiols and organic solvents, and operates under mild conditions, thereby offering considerable potential for applications in organic synthesis.