Microalbuminuria (MA) detects subjects at risk for cardiovascular disease (CVD) and chronic kidney disease (CKD) among diabetics, hypertensives and the general population. There is still a paucity of data on prevalence and risk factors for MA in the UK. We examined in a cross-sectional study, the prevalence and risk factors for MA in the general population of Sheffield, UK. The study was conducted among participants of the Kidney Evaluation and Awareness Program in Sheffield (KEAPS), a population-based screening program for MA. The screening tools included a questionnaire collating information on demographics, lifestyle, medical and family history of diabetes mellitus, hypertension and CKD. MA measurements were obtained by immunonephelometry, and MA thresholds were defined using the albumin-creatinine ratio. The prevalence of MA was 7.1% in a random sample of a Sheffield-based population screened only once. The prevalence was 6.2% in the non-diabetic and non-hypertensive subjects. The prevalence of MA was only 1.3% in the subjects without any known risk factor, such as old age, diabetes, hypertension, obesity or CVD. The prevalence of MA could be overestimated as it was based on a single albumin-creatinine ratio testing. The independent predictor variables associated with the presence of MA in a mutually adjusted logistic regression model were: age (OR = 1.012, 95% CI: 1.00-1.02), diabetes (OR = 3.25, 95% CI: 1.30-8.13), obesity (OR = 4.09, 95% CI: 1.71-9.80) and family history of hypertension (OR = 1.87, 95% CI: 1.00-3.47). The main determinants of MA were increased age, diabetes, obesity and family history of hypertension. On the population level, obesity as a risk factor for MA is less well documented; in this study obesity had greater odds for MA than diabetes and hypertension.