Noncommunicable diseases (NCDs) are rising as a share of disease burden in low- and middle-income countries where out-of-pocket (OOP) payments are a major source of health financing. To realize universal health coverage (UHC) aims, health systems may need to better protect people from the financial risks of NCDs and ensure OOP costs do not restrict access to NCD health services. This dissertation aimed to assess: cross-country differences in the catastrophic health expenditure (CHE) caused by NCDs versus other disease areas; how OOP spending and utilization patterns differed for CHE cases caused by NCDs versus other disease areas; and whether the elimination of OOP costs can increase uptake and reduce disparities in coverage of NCD health services. Two cross-country household surveys were used, the World Health Surveys (Chapter II) and the Study on Global Aging and Adult Health (Chapter III), as was high-frequency insurance claims data, the Maine Health Data Organization All Payer Claims Database (Chapter IV). Quantitative methods included cross-sectional regressions (Chapter II), machine learning (Chapter III), and quasi-experimental methods (Chapter IV). This dissertation showed that NCD OOP spending is both a threat and opportunity for UHC. First, Chapter II showed that the association between heart disease CHE and prevalence was strong and robust to key controls, suggesting that as NCDs comprise a larger share of disease burden, they could pose a threat to financial risk protection. Chapter III showed that OOP spending per visit was twice as high for NCDs as communicable diseases and CHE caused by NCDs was more likely to be caused by the culmination of spending over many visits, rather than a single health spending shock. Finally, Chapter IV showed that eliminating the OOP costs of preventive colonoscopies increased utilization substantially more in rural areas than in urban areas, reducing disparities significantly. Overall, these results underscore that the rising share of disease burden caused by NCDs may pose new challenges for financial risk protection, service coverage, and the equity of UHC. Targeting reforms to how OOP spending on NCDs affects populations, and how that differs from other health focus areas, may help countries pursue UHC cost-effectively.