The awareness of sustainability and widespread utilization of green technologies in textile dye houses are revolutionizing not only textile industries but related fields. The current study is concerned with ultrasonic (US)-assisted utilization of extracts of Alkanna tinctoria (a source of natural alkanin dye) for wool dyeing. The extracts are obtained in various media, and both extracts and wool fabrics have been  US treated for 15–60 min. Dyeing is performed by applying variable parameters and utilizing herbal-based extracts as a source of bio-mordant, hence improving the fastness rating and enhancing color strength. Good color strength and fastness ratings are obtained using irradiated extract at 4 pH when the US-treated wool fabric is dyed at 65 °C for 60 min before and after chemical and bio-mordanting. For comparative studies, chemical mordants are also employed. In contrast to chemical mordants, the bio-mordants have made the dyeing process more sustainable with good to excellent fastness rating. Graphical Abstract