A device for inserting a cannula of a subcutaneous infusion device into a subcutaneous layer of skin of a patient. For example, some devices automatically retract a needle used to introduce the cannula of a subcutaneous infusion device into the subcutaneous layer of skin of a patient. The device can include a housing with an internal cavity, as well as a needle coupled to the housing. The needle can be coupled to a cannula of a subcutaneous infusion device. A member can move the needle. Upon full introduction of the needle and associated cannula of the subcutaneous infusion device into a subcutaneous layer of skin of a patient, the member is automatically actuated to move the needle into the internal cavity of the housing into the retracted state while leaving the cannula of the subcutaneous infusion device in the subcutaneous layer of skin of the patient.