Excessive consumption of sweetened beverages (SBs) poses significant health and fiscal challenges under the Philippines’ healthcare system. This study examines the current SB tax regime established under Republic Act (RA) 10963 and the proposed amendments through House Bill (HB) 5003, with a focus on their efficiency, welfare, and fairness implications. Using elasticity-based projections, the paper estimates the potential revenue impact of the proposed tax increase and evaluates the effectiveness of volumetric taxation in promoting healthier consumer choices. The analysis finds that volume-based taxation inadequately reflects differences in sugar content and therefore fails to meaningfully influence consumer behavior and encourage responsible decision-making in the consumption of SBs. A concerted shift toward a tax based on sugar content, complemented by carefully calibrated information and behavioral interventions, is recommended to achieve more equitable health and fiscal outcomes.