<p>Excess sugar-sweetened beverage (SSB) intake contributes to obesity and non-communicable diseases in Malaysia, yet little is known about consumers’ knowledge, beliefs, and practices in tea and coffee retail chains and their link to intake. A cross-sectional survey was conducted among 303 young adults in Malaysia (91 males, 212 females; median age 20 ± 2 years). The questionnaire assessed sociodemographics, purchasing habits, and SSB-related knowledge, beliefs, and practices, while habitual intake was measured using a validated beverage frequency questionnaire covering 26 beverages categorised as SSBs or non-SSBs. Associations between knowledge, beliefs, practices, and intake categories were analysed using Chi-square tests, and predictors of beverage intake were identified via multiple linear regression. Most participants (86.1%) had “good” knowledge, but only 16.8% had “good” beliefs, and 53.5% had “good” practices. The median daily SSB intake was 449.1 ± 761.1&#xa0;ml, with participants distributed across low, moderate, and high intake categories based on quartiles. Poorer tea/coffee practices were associated with higher SSB intake (<i>p</i> = 0.009), while knowledge and beliefs showed no association. Weekly fast-food consumption predicted higher SSB intake (B = 183.7&#xa0;ml/day, <i>p</i> = 0.009). For non-SSB intake, older age (<i>p</i> = 0.022) and higher physical activity (<i>p</i> = 0.011) were positive predictors, while smoking was negative (<i>p</i> = 0.031). Young adults in Malaysia show high SSB risk awareness but limited accurate beliefs and healthy practices. Behavioural factors, particularly fast-food intake, influence SSB consumption more than knowledge, implicating retail-based interventions over education alone in reducing SSB intake.</p>