Aim : The objective of the study was to evaluate and compare the effect of a soft drink and a fresh fruit juice on the microleakage of flowable composite and resin modified glass lonomer cement (RMGIC). Methods and materials : 70 non-carious human premolars were collected and stored in saline until further use. Class-V cavities were prepared and restored with RMGIC on the buccal surface and flowable composite on the lingual surface for evaluating microleakage. The experimental groups (Group I and II ) comprised of 60 teeth, while the remaining 10 formed the control group (Group III—Water). The experimental groups were further divided into 2 groups (Group I—Cola drink and Group II—Fresh orange fruit juice) of 30 teeth each. Each group was then further divided into 3 subgroups (Short, Medium and Long-immersion) containing 10 teeth as shown in flow chart. Immersion regime was followed according to Maupome G et al and microleakage was evaluated by using Rhodamine B dye and examined under stereomicroscope. Results : Microleakage data obtained was statistically analyzed by Chi-square test. The teeth showed statistically significant microleakage as the immersion regime increased. Interpretation and Conclusion : Low pH soft drink caused highly significant microleakage at the tooth and restorative material interface in medium and high immersion regimes signifying that the leakage pattern was directly proportional to the number of immersions. Thus, the study conclusively proves that the ‘sipping habit’ associated with commonly available low pH beverages is detrimental to the longevity of restorations.