Bond funds are divided according to the degree of openness, and the mainstream is regular open-end bond funds and closed-end bond funds. Closed-end bond funds refer to bond funds that enter a closed period after issuance, during which bondholders may not redeem the funds in advance; Closed-end bond funds are more open than closed-end bond funds, and adopt the operation mode of "closed management+regular opening". Bondholders are not allowed to redeem during the closed management period, and can redeem the fund at any time after the management period ends.

The biggest feature of regularly opening bond funds is to enter an open period after each closed period. The opening period is not less than one week, and the longest is not more than one month. The closed period and the open period are operated separately. This regular open operation mode ensures the relative stability of the fund scale, avoids the influx of funds to dilute the interests of the original holders, and also avoids the pressure of fund redemption during the closed period. Compared with other common open-end funds, fixed-term open-end bond funds can further improve the expected annualized expected return of investment through repurchase operation and portfolio leverage due to closed operation.

After each closed operation period, most products are arranged to be open for no less than 5 working days and no more than 20 working days, which can meet the redemption needs of investors. For example, the Galaxy Year-end Return Fund is restricted to open once every quarter except for 5 to 20 working days each year.

Compared with regular open bond funds, closed bond funds of bond funds have more advantages in liquidity except the time difference of closed period. Closed-end bond funds are not liquid. The emergence of regular open bond funds can not only help investors enjoy the expected annualized expected return of closed-end bond funds, but also improve liquidity.