Recently, non-conventional sources of mucilage have gained significant attention due to their exceptional techno-functional properties and easy availability. This study aimed to utilize Cordia dichotoma fruit mucilage (CDM) for fabricating bioactive films to evaluate the shelf-life of bread. For the development of nanoemulsion, different concentrations of flaxseed oil (1–5% w/w) were employed. Selection was carried out based on droplet size, encapsulation efficiency, and antimicrobial activity. The selected nanoemulsion (CDM-FO1) was subsequently used to develop CDM-based films with the incorporation of carboxymethyl cellulose (CMC) and sodium alginate (SA). Results revealed that the droplet size of the nanoemulsions was significantly increased from 101.25 ± 4.68 nm to 205.15 ± 7.14 nm with increasing flaxseed oil concentration. However, the addition of CMC and SA improved the tensile strength (13.97 ± 0.34 MPa) of the CDM-F11 film compared to control films CDM (6.98 ± 0.68 MPa) and CDM-FC (7.76 ± 1.65 MPa). The CDM-F11 film exhibited excellent barrier properties compared to the control film. The control film showed higher yeast and mold growth, starting at 0.84 ± 0.57 Log CFU/g on the 3rd day and increased to 3.12 ± 0.39 Log CFU/g by the 9th day. In contrast, the CDM-FC film demonstrated better antimicrobial properties, with microbial growth at 0.52 ± 0.39 Log CFU/g on the 3rd day and 2.84 ± 0.38 Log CFU/g on the 9th day. Overall, CDM film loaded with flaxseed oil nanoemulsion can be effectively used as a sustainable food packaging material with enhanced antimicrobial efficiency for bread preservation.