A reconfigurable narrow‐frame coupled‐loop antenna capable of providing hepta‐band long term evolution/wireless wide area network (LTE/WWAN) for metal‐rimmed smartphone applications is proposed. The ground clearance of this proposed antenna is only 7 × 70 mm2 which is promising for narrow‐frame smartphone applications. Moreover, this proposed antenna can realise the miniaturisation by employing a positive intrinsic negative diode (PIN diode), which can provide two working states. When the PIN diode is OFF, it can provide coverage for GSM850/DCS/PCS/UMTS2100/LTE2300/2500 operations. When the PIN diode is ON, the obtained bands are GSM900/DCS/PCS/UMTS2100/LTE2300/2500. Hence, by combining these two working states, GSM850/900/DCS/PCS/UMTS2100/LTE2300/2500 operations are achieved. In addition, the feasibility of realising decoupled multi‐antennas is demonstrated and its performances are well‐suited for future smartphone applications. Detailed design considerations of the proposed antenna are described. Both experimental and simulated results are also presented and discussed.