Oral hygiene is essential for maintaining general health and boosting social confidence. Mouthwash serves as an effective supplement to daily brushing and flossing by reducing oral microbial load, controlling bad breath, and promoting a sensation of freshness. This study aimed to formulate and evaluate a mouthwash specifically designed to enhance oral freshness using a combination of herbal and synthetic ingredients. The formulation included peppermint oil, glycerin, sodium benzoate, ethanol, citric acid, and purified water. The prepared mouthwash was assessed for organoleptic properties (color, odor, taste, clarity), physicochemical characteristics (pH, viscosity, specific gravity), and antimicrobial activity against Streptococcus mutans. Stability testing was conducted under ambient conditions to evaluate shelf-life and formulation integrity. Results showed that the mouthwash exhibited acceptable organoleptic qualities and maintained a suitable pH range of 5.5–6.5. It demonstrated effective antimicrobial action, with notable zones of inhibition in agar diffusion tests. The formulation remained stable during the testing period with no significant changes in physical or chemical properties. Overall, the formulated mouthwash proved effective in delivering oral freshness and may serve as a promising alternative to existing commercial products.