The War on Diabetes campaign was launched in 2016, encouraging Singapore residents to engage in regular exercise, adopt healthy dietary habits and screen for early detection of diabetes. This study aims to examine campaign awareness and its associations with sedentary behaviour, dietary habits and identifying diabetes. Data were obtained from the nationwide Knowledge, Attitudes and Practices study on diabetes in Singapore. A total of 2895 participants responded to a single question assessing campaign awareness. The Dietary Approaches to Stop Hypertension (DASH) diet screener assessed dietary habits, and the Global Physical Activity Questionnaire (GPAQ) measured sedentary behaviour. Recognition of diabetes was established using a vignette depicting a person with diabetes mellitus. Logistic and linear regression models were used to measure the associations. Most participants were 18- to 34-years old (29.9%) and females (51.6%). About 57.4% identified the campaign. Campaign awareness exhibited positive associations with identifying diabetes based on the vignette [odds ratio (OR): 1.5; 95% confidence interval (CI): 1.1-2.2; P = 0.022], lower odds of sedentary behaviour [greater than or equal to] 7 h/day (OR: 0.7; CI: 0.5-0.9; P = 0.018) and higher DASH scores ([beta] = 1.3; P < 0.001). The study recognized early significant associations between the behavioural outcomes and the campaign, emphasizing the need for ongoing campaign sustainability and evaluation of its long-term impact on population health.