A copper‐catalyzed ring‐opening cross‐coupling of cyclopropanols with phosphorothioates has been developed. This method efficiently affords diverse γ‐carbonyl thiophosphates in medium to high yields under mild conditions. Herein, further studies demonstrate that these thiophosphates can be transformed into thiacyclobutanes with moderate efficiency. Initial mechanistic investigations suggest that the reaction proceeds via a radical pathway or homoenolate intermediate, rather than a Michael addition mechanism.