Local biomass of toothfish in research blocks in Subareas 48.6 and 58.4 have been estimated using a CPUE-by-seabed-area analogy method and Chapman tag-recapture methods following the advice of WG-SAM. The trend analysis decision rules developed by WG-FSA 17 were applied to provide catch limits for 2018/19. The only research blocks in which there were adequate recaptures were 486_2, 486_3 and 486_4. However, as the trend in all three of these research blocks was declining the revised catch limit is determined as 0.8 times the existing catch limit. The revised catch limits for all but one of the research blocks was determined by the requirement that the absolute change in the existing catch limit should not exceed 20%.