This dataset presents results of benefit-cost analyses of different adaptation objectives using grey infrastructure to coastal flooding at the global scale. The four adaptation objectives are: (1) ‘Protection constant’, which keeps protection levels in the future the same as current protection levels; (2) ‘Absolute risk constant’, which calculates future protection standards when the absolute value for expected annual damage is kept the same as current; (3) ‘Relative risk constant’, which calculates future protection standards when expected annual damage as a percentage of GDP is kept the same as current; and (4) ‘Optimize’, which calculates future protection standards by maximizing net present value. The results for each adaptation objective include future protection standards, change in risk relative to GDP, benefit-cost ratio and net present value for various RCP-SSP combinations for sub-national regions.