Abstract The transient response of a thin wire in the presence of a half-space is calculated with a new formulation of the Method of Moments (MoM) in time domain, based on a novel Time-Domain Mixed Potential Integral Equation (TD-MPIE), using complex-time Green's functions. The excitation is a Gaussian voltage source and the solution is obtained by using a Marching-On-in-Time (MOT) procedure. Band-Limited Quadratic B-spline (BL-QB) functions are used as Temporal Basis Functions (TBFs). They are compared with Band-Limited Linear B-spline (BL-LB) interpolation functions. Numerical results show that the solution using BL-QB TBFs is stable and accurate, without late-time instabilities, and efficient in terms of memory usage and computation time.