The formation of Antarctic Bottom Water (AABW) is a key process in the global ocean circulation, but modelling the formation and downslope flow of AABW represents an ongoing challenge for ocean and climate models due to the high horizontal resolution required. Here, we assess the formation and export of AABW to the abyss and its sensitivity to horizontal model resolution in a circumpolar ocean-sea ice model available at horizontal resolutions of 1/10°, 1/20° and 1/40°. The AABW transport across the 1000 m isobath of the Antarctic continental slope increases by 27% with 1/20° resolution compared to 1/10°, but there is no further transport increase at 1/40° resolution. This resolution dependency is strongest in the Ross and Weddell Seas, the two most important regions of AABW formation. The higher AABW export at 1/20° compared to 1/10° resolution is due to formation of denser waters on the continental shelf and less diapycnal mixing during the downslope flow. This has effects downstream in the abyss of the Australian Antarctic Basin which is better ventilated in the 1/20° case. We conclude that a horizontal resolution of 1/20° is sufficient to simulate AABW formation and export, in agreement with theory of the downslope flow of dense plumes.