An ostomy appliance for receiving waste is described including: first and second walls connected to each other at or near their peripheries, the first wall having a stoma-receiving opening; a waste collecting cavity defined between the first and second walls; a first weld portion positioned to one side of the appliance and which connects the first and second walls together, which first weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance; and a second weld portion positioned on an opposite side of the appliance to the first weld portion and which connects the first and second walls together, which second weld portion extends away from a periphery of the appliance and downwardly towards a bottom of the appliance.