Hypertensive disorders of pregnancy (HDP) complicate 5–10% of pregnancies, with resultant lifelong increased risks of cardiovascular disease (CVD). We aimed to describe lifestyle behaviours at 6 months post-HDP in four HDP subgroups, and their association with markers of cardiometabolic health. Subgroups were chronic hypertension (CH), gestational hypertension (GH), preeclampsia, and preeclampsia superimposed on chronic hypertension (CH + PE). The BP2 study is a multi-site, three-arm, randomised controlled trial. At 6 months postpartum, the NSW Population Health Survey and BP2 surveys collected lifestyle behaviours and demographic data. Body mass index (BMI), waist circumference, and blood pressure (BP) were also assessed. Descriptive statistics, ANOVA and Spearman’s correlation coefficients were used. Of 484 women (16% CH, 23% GH, 55% preeclampsia, and 6% CH + PE), 62% were overweight or obese. Only 6% met the recommended five vegetable and two fruit serves per day, and 43% did not meet the recommended 150 min of moderate–vigorous physical activity in five sessions per week. Adherence to both diet and physical activity recommendations was correlated with more favourable cardiometabolic outcomes, including lower BMI, waist circumference, and systolic and diastolic BP. Lifestyle interventions that improve diet and physical activity post-HDP are needed to reduce BP, BMI, and long-term CVD in this high-risk population.