Ascertaining command completion in flash memories is disclosed. An exemplary aspect includes eliminating the software lock and the outstanding requests variable and replacing them with a transfer request completion register. The transfer request completion register may be mapped to the universal flash storage (UFS) Transfer Protocol (UTP) Transfer Request List (UTRL) slots. The controller of the host—a hardware component—may set the bit in the transfer request completion register on transfer request completion at the same time the doorbell register is cleared. After this bit has been read, the bit in the transfer request completion register is cleared.