The study of spinning charged particle dynamics around black holes in external fields offers insights into relativistic motion and the influence of spin-curvature and electromagnetic interactions. In this work, we investigate the motion of spinning charged test particles in the vicinity of Schwarzschild black holes immersed in asymptotically uniform magnetic fields. Using the Mathisson–Papapetrou–Dixon (MPD) equations, we derive the equations of motion and analyze the superluminal bound, which constrains the physically admissible values of the spin parameter. We investigate how this bound depends on the magnetic interaction parameter ω, which couples the particle’s charge to the external magnetic field. Furthermore, we explore the effective potential and examine how both spin and ω affect circular orbits and the dynamics of the particle. Our results reveal the nonlinear interplay between spin, curvature, and magnetic interaction, contributing to the broader understanding of charged spinning test particle motion in magnetized relativistic environments