In this work, the proposed design utilizes a complementary split ring resonator (CSRR) loaded ground plane to enhance the return loss of a microstrip patch antenna.The addition of CSRR slots on the ground plane resulted in an improvement in the return loss of the microstrip patch antenna. The proposed antenna has undergone the stages of design, fabrication, and testing. The measured results exhibit a high level of conformity with the simulation results. The proposed antenna has a size of 99 × 55 × 1.6mm 3. The measured impedance 1 Springer Nature 2021 L A T E X template A Compact Metamaterial Loaded MIMO Antenna for Sub-6GHz 5G Applications bandwidth is 24.18 (return loss< −10 db) from 3.29 to 4.2 GHz. The designed antenna is suitable for applications within the Industrial Scientific Medical(ISM) band. The H-plane radiation pattern of the antenna was directional, while the E-plane radiation pattern was bidirectional. To achieve optimal outcomes, a parametric investigation of the CSRR was conducted. Alternatively, researchers carried out a study on various parameters of the CSRR to determine the most favorable results. The proposed antenna exhibits a straightforward design, displays a desirable radiation pattern, and boasts a gain of 2.63 dBi when operating at its resonant frequency. Additionally, a size reduction of 10% was attained without compromising its performance, and the bandwidth slightly surpasses that of the unloaded antenna.