An infusion system includes a disposable wearable infusion device and a filler device. The disposable infusion device has a body arranged to be adhered to a patients skin and a reservoir for holding a liquid medicant to be infused into the patient. The filler device is arranged to detachably receive the infusion device body and to transfer a volume of the liquid medicant to the infusion device reservoir. The filler device may be part of a service device arranged to detachably receive the infusion device and which also includes a cannula driver and a cannula for providing the infusion device with a cannula and deploying the cannula to beneath a patients skin.
