<p>This study explores the influence of Brownian motion and thermophoresis on heat and mass transfer characteristics of a viscoelastic, chemically reactive magnetite fluid flow over a stretching sheet. The motivation of present study originates to improve the thermal and mass transport efficiency in biomedical and industrial processes including viscoelastic magnetic fluid, where thermophoresis and Brownian motion significantly govern the species diffusion and heat transfer. The governing nonlinear partial differential equations are transformed into ordinary differential equations using similarity transformations. Numerical solutions are obtained using the Bvp4c solver in MATLAB. The investigation incorporates key effects of physical parameters such as thermal radiation, free convection, suction and slip velocity on heat and mass distributions with fluid flow. Velocity and temperature increase with higher viscoelastic and porosity parameters. While the Sherwood and Nusselt numbers increase, and the skin friction coefficient decreases with increasing viscoelastic parameter values. This non-Newtonian model has extensive applications in engineering and industries, including paper manufacturing, fibres technology, food processing, geothermal energy extraction, wire coating and lubricants.</p>