A removable antenna is provided for an electronic device such as a laptop computer. An antenna resonating element is mounted within the antenna. Magnetic coupling structures are used to magnetically attach the antenna to the electronic device. The magnetic coupling structures couple the antenna resonating element to circuitry in the electronic device. The electronic device may have an antenna receptacle that holds the antenna in a stowed position and allows the antenna to extend to an extended position. A user may extend the antenna by sliding the antenna or by rotating the antenna to its extended position. The coupling structures may allow the antenna to break away from the electronic device without damage.