The last few years have seen a growing commitment worldwide to universal health coverage (UHC). Yet there is a lack of clarity on how to measure progress towards UHC. We propose a ‘mashup’ index that captures both aspects of UHC: that everyone—irrespective of their ability-to-pay—gets the health services they need; and that nobody suffers undue financial hardship as a result of receiving care. We break service coverage into prevention and treatment, and financial protection into impoverishment and catastrophic spending; we use nationally representative household survey data to adjust population averages to capture inequalities between the poor and better off; we allow non-linear trade-offs between and within the two dimensions of the UHC index; and we express all indicators such that scores run from 0 to 100, and higher scores are better. In a sample of 24 countries for which we have detailed information on UHC-inspired reforms, we find a cluster of high-performing countries with UHC scores of between 79 and 84 (Brazil, Colombia, Costa Rica, Mexico, and South Africa) and a cluster of low-performing countries with UHC scores in the range 35–57 (Ethiopia, Guatemala, India, Indonesia, and Vietnam). We find that countries have mostly improved their UHC scores between the earliest and latest years for which we have data—by about 5 points on average. However, the improvement has come from increases in receipt of key health interventions, not from reductions in the incidence of out-of-pocket payments on welfare.