Suiko was divided into two groups under the Ritsuryo system (a system of centralized government based on the Ritsuryo codes): one was the official Suiko (Ku-Suiko) and the other was the private Suiko (Shi-Suiko).
律令制においては、公的な出挙（公出挙：くすいこ）・私的な出挙（私出挙：しすいこ）に区分された。