Background The purpose of this in vitro investigation was to evaluate the impact of five distinct commercial mouthwashes on the development of Candida albicans that had been adhered to heat-cured acrylic resin sheets. Methods This in vitro investigation was carried out at the MES Medical College's Microbiology Department in Perinthalmanna, Kerala, India. A total of 72 heat-cured acrylic resin sheets, size 10 × 10 × 2 mm, were fabricated. After disinfection, all 72 acrylic sheets were placed in a flask containing a suspension of the standard strain of Candida species (American Type Culture Collection) and incubated at 37ºC for 24 hours. Then, the acrylic sheets were randomly divided into six groups, with each group containing 12 acrylic sheets. Group 1 was the control group to which no mouthwash was added. In group 2, Colgate Plax was added. In group 3, Hiora Himalaya was added. In group 4, Oral B was added. In group 5, Listerine was added. In group 6, Pepsodent was added. Colony-forming units (CFUs) were assessed using a colony counter every six, 24, 48, and 120 hours. After obtaining the pH and CFU of all 72 specimens, software known as the Statistical Package for Social Sciences (SPSS) (IBM Corp., Armonk, NY) was used to analyze the data. Results Candida albicans adhered to heat-cured denture base acrylic resin sheets differed significantly in response to commercially available mouthwashes (Oral B, Colgate Plax, and Pepsodent) and non-commercial mouthwashes (Hiora Himalaya and Listerine) that contained cetylpyridinium chloride. Conclusions Compared to other mouthwashes that do not contain cetylpyridinium chloride (Listerine and Hiora Himalaya), mouthwashes with cetylpyridinium chloride as the active ingredient (Oral B, Pepsodent, and Colgate Plax) have shown good antifungal properties against the adhering Candida albicans on denture base resin.