A gate current partition scheme for Schottky gate GaN-based high-electron-mobility transistors (HEMTs) using a charge-based approach is proposed. Analytical expressions for gate-to-drain and gate-to-source components of Fowler-Nordheim tunneling (FNT), Poole-Frenkel emission (PFE), thermionic emission (TE), and defect assisted tunneling (DAT) currents are derived. This current partition model is implemented in Verilog-A and validated with experimental results for a wide range of gate and drain bias. The model also passes the symmetry test. © 1963-2012 IEEE.