AimsTo estimate prevalence of diagnosed (dDM) and undiagnosed diabetes (uDM) in Hungary and investigate determinants of uDM. MethodsData was obtained from the nationally representative H-UNCOVER study. As laboratory measurements were available for 11/19 Hungarian counties, n = 5,974/17,787 people were eligible. After exclusions, 5,673 (representing 4,976,097 people) were included. dDM was defined by self-reporting, while uDM as negative self-reporting and elevated fasting glucose (≥7 mmol/l) and/or HbA1c (≥48 mmol/mol). Logistic regression for complex samples was used to calculate comparisons between dDM and uDM adjusted for age and BMI. ResultsDiabetes prevalence was 12.0 %/11.9 % (women/men, 95 %CI:10.7–13.4 %/10.7–13.2 %), while 2.2 %/2.8 % (1.7–2.8 %/2.2–3.6 %) of women/men were uDM. While the proportion of uDM vs. dDM was similar for women ≥ 40, men in their forties had the highest odds for uDM. Neither unemployment (women/men OR:0.58 [0.14–2.45]/0.50 [0.13–1.92]), nor education level (tertiary vs. primary; women/men OR: 1.16 [0.53–2.56]/ 0.53 [0.24–1.18]) were associated with uDM. The risk of uDM was lower in both sexes with chronic morbidities. ConclusionsWe report higher prevalence of diabetes and undiagnosed diabetes than previous Hungarian estimates. The finding that socioeconomic factors are not associated to uDM suggests that universal health care could provide equitable access to diabetes diagnosis.