In this study, a multiband 8-element MIMO antenna operating at LTE 800/2300/2500 MHz, GSM 850/900/1900 MHz, UMTS, DCS, PCS, IMT, WLAN 2400 MHz, WiMAX 3500 MHz and Wi-Fi 5800 MHz is proposed for handheld devices. The proposed antenna comprises of radiating elements and novel decoupling structure to reduce the mutual coupling. To obtain multiple resonances, F-shaped monopole, C-shaped strips, L and S-shaped monopoles are integrated to form the complete radiator. The protruded ground plane with inverted π-shaped slot acts as the decoupling element. The eight elements are arranged in a certain fashion to achieve spatial and polarisation diversity. The impedance bandwidth achieved is 170, 1070, 400 and 700 MHz. The isolation is >20 dB in all the desired operating bands. The simulated peak gain and efficiency of the antenna at the four operating bands are 4.8/6.3/5.4/4.7 dBi and 75/90/80/83%, respectively. Furthermore, the envelope correlation coefficient, the apparent diversity gain and effective diversity gain are calculated and presented. The obtained measured and simulated results are in good correlation with each other. © The Institution of Engineering and Technology 2019.