Copper canisters for nuclear waste containment can be expected to be exposed to temperatures up to 100°C. Since the material is pure copper, creep properties must be taken into account in particular for the welded joints in the canisters. In the paper creep rupture properties of parent metal, weld metal, and simulated heat affected zone are presented for 110°C. About ten times shorter rupture times were found for the weld metal in comparison to the parent metal. Cross weld specimens showed even shorter rupture times.