In the 25 years from 1990 to 2015, annual global carbon emissions grew by 60%, approximately doubling total global cumulative emissions. This has brought the world perilously close to exceeding 2°C of warming, and it is now on the verge of exceeding 1.5°C. This paper examines the starkly different contributions of different income groups to carbon emissions in this period. It draws on new data that provides much improved insight into global and national income inequality, combined with national consumption emissions over this 25-year period, to provide an analysis relating emissions to income levels for the populations of 117 countries. Future scenarios of carbon inequality are also presented based on different possible trajectories of economic growth and carbon emissions, highlighting the challenge of ensuring a more equitable distribution of the remaining and rapidly diminishing global carbon budget.