This paper presents a gap coupled triple band slot loaded microstrip patch antenna with parasitic patches. It consist inverted U‐shape and inverted T‐shape open‐ended slots along with a rectangular slot at center of patch. The inverted U‐shape open‐ended slot generates a driven patch at bottom side and an inverted U‐shape parasitic patch at middle side of patch while inverted T‐shape open‐ended slot generates two rectangular shape parasitic patches of same dimension at top side of patch. The proposed gap coupled antenna covers 2.29 to 2.77 GHz in first band, 3.25 to 3.65 GHz in second band and 4.67 to 5.72 GHz in third band with return losses of −23.2, −19.90, and −38.06 dB, respectively. The proposed antenna resonates at 2.57, 3.48, and 5.37 GHz with fractional bandwidth of 18.97% (480 MHz), 11.59% (400 MHz), and 20.21% (1050 MHz), respectively. The return loss and bandwidth of presented antenna is increases gradually by loading inverted U‐shape and inverted T‐shape open‐ended slots along with a rectangular slot in antenna patch. The proposed antenna exhibits stable peak gain of 4.45, 4.81, and 5.26 dBi and efficiency of 89.5%, 89%, and 90% in three resonating bands. The antenna resonating bands are applicable for WiMAX: 2.5/3.5/5.5 GHz (2.5–2.69, 3.4–3.69, and 5.25–5.85 GHz), WLAN: 2.4/5.2 GHz (2.4–2.484 and 5.15–5.35 GHz) and sub‐6 GHz 5G: 3.5 GHz (3.3–3.8 GHz). The size of antenna is 40 mm × 50 mm (0.34 × at frequency 2.57 GHz). The gap coupled antenna geometry is fed by microstrip line feed and simulated by IE3D simulation tool.