The present work introduces a miniaturized microstrip patch antenna meticulously engineered for wireless energy transmission systems. To accomplish spurious harmonic suppression, the proposed configuration incorporates an open-circuited stub along the feed line, effectively mitigating undesired resonant modes up to the fourth harmonic order. The antenna, precisely optimized to operate at 2.45 GHz, demonstrates a 10-dB return-loss impedance bandwidth ranging from 2.3 GHz to 2.5 GHz (8.69%), with a simulated gain of 2.2 dBi and a radiation efficiency exceeding 75%. Owing to these distinguished electromagnetic attributes, the proposed antenna emerges as a potential solution for wireless power transfer (WPT) end-use systems, where compactness, spectral purity, and high efficiency are of critical importance.