"The development of novel routes for the production of functional textiles is an urgent need. Natural dyes are a safe and sustainable choice for the colouration of textiles. To achieve the colouration of textiles with natural dyes, mordanting methods have been highly explored; the present work targets the functional natural dyeing of cotton by the in-situ development of azoic dye. The paper discusses a new application approach of a novel natural dye (derived from conical prickles of Bombax ceiba bark) to cotton using mosquito repellent ethyl anthranilate. The dye obtained from the extract of Bombax ceiba bark conical prickles (CPBCE) was further converted into azoic dye by reacting it with diazotised ethyl anthranilate. The developed coloured cotton fabric was endowed with mosquito repellence, antibacterial action, and UV protection. The colouration properties and fastness of dyed samples were examined using standard methods. Moreover, the dyed samples were also characterised using TGA (thermogravimetric analysis) and XRD (X-ray diffraction) analysis. Thus, 100% mosquito repellent properties, good antibacterial protection, and excellent UV protection were imparted to cotton."