The increasing demand for sustainable barrier coatings in packaging, driven by the principles of the circular bioeconomy and the urgency to mitigate plastic pollution, necessitates the development of innovative, bio-based alternatives to conventional plastics [1–3]. In this study, we present the development of bio-based latexes derived from galactoglucomannan (GGM), a softwood-derived hemicellulose, for application in packaging barrier coatings. Modified GGM was employed as a non-ionic surfactant and co-monomer during the emulsion polymerisation of butyl acrylate, a monomer that can be sourced from renewable feedstocks such as sugarcane or corn, thereby eliminating the need for fossil-derived surfactants [4]. The polymerization process utilized a 1:1 ratio of GGM modified with allyl glycidyl ether and butyl acrylate monomer, achieving a polymerization conversion of 90% within five minutes. This high conversion efficiency significantly enhances process productivity and reduces energy consumption. The resulting latexes were subsequently cast into films, which exhibited promising barrier properties, including an oxygen transmission rate of 10 cm³/m²/day and a water vapour transmission rate of 80 g/m²/day. These findings highlight the potential of GGM-based latexes as effective and sustainable alternatives to conventional packaging materials, thereby contributing to the advancement of bio-based solutions within a circular economy framework.