Universal health coverage (UHC) is a key policy issue in countries of the World Health Organization (WHO) South-East Asia Region. However, despite projections of significant increases in burden, there is little protection against the financial risks associated with noncommunicable diseases (NCDs), including diabetes. Thailand achieved UHC of all 67 million of the population in 2002, under three public health insurance schemes. The country therefore provides a case-study on diabetes prevention and care in the context of UHC. Although the budget for the Thai Universal Coverage (UC) scheme, which covers nearly 80% of the population, increased significantly during 2003-2013, the proportion allocated to clinical prevention and health promotion declined from 15% to 11%. The financial case for investment in diabetes prevention is made, particularly with respect to a focus on primary care and the use of community volunteers. The UC scheme can expand to nearly 100% population coverage, with a comprehensive benefit package and financial risk protection. Although the rates of complications and fatalities in patients with diabetes have improved over the last few years, achievement of well-controlled fasting blood glucose for all patients is still the main challenge for further improvement. It is recommended that, in order to improve coverage of diabetes care and prevention, it is essential for countries in the WHO South-East Asia Region to include major NCD services, in particular primary prevention, in their UHC strategies. Since a resilient health system is key to UHC delivery, strengthening of the health workforce and infrastructure should be part of any action plan to prevent and control diabetes.