Abstract: A transaction system, comprising: a first-grade account, wherein the first-grade account is a platform-grade master account which is configured to receive external imported funds and can distribute the external imported funds to a second-grade account; the second-grade account is configured to receive the funds distributed by the first-grade account, and can distribute the received funds distributed by the first-grade account to a third-grade account; the third-grade account is configured to undertake a user-oriented transaction service; wherein when the transaction service undertaken by the third-grade account is a withdrawal service, a withdrawal amount is deducted from the third-grade account; and when the withdrawal amount deducted from the third-grade account is less than a total withdrawal amount corresponding to a current withdrawal service, the second-grade account is requested to retrieve a first residual withdrawal amount which is an amount obtained by subtracting the withdrawal amount deducted from