We propose an approach for projecting future absolute intergenerational income mobility. This approach combines the ‘copula and marginals’ approach for examining historical trends, with existing projections of national income and population. A key insight is that half of the required data (the marginal income distribution of parents) are already observable. We apply this approach to 28 OECD countries under two scenarios: (i) projected income growth with no change to inequality, and (ii) income growth combined with extrapolations of inequality trends. We also produce historical absolute mobility estimates, including for 16 countries where none previously existed to our knowledge. The results show significant historical declines in mobility for most countries. The projections suggest potential recovery under sustained economic growth, but rising inequality systematically attenuates these gains.