Systems, methods and devices are described herein for adjusting the insertion depth of a cannula associated with a portable therapeutic device within the body of a patient. The systems may include a mounting unit securable to the skin of the patient and having a mounting base and a well defining a passageway through the mounting base and a cannula unit including a cannula subcutaneously insertable through the well of the mounting unit.The well may have an adjustable height and/or adjustable anchoring mechanisms that allow for varying and customized insertion depths of the cannula within the body of the patient.