The U-slot patch antenna, a single-layer single-patch antenna on a relatively thick substrate$(sim 0.08lambda _0)$, is a wide-band antenna with an impedance bandwidth in a range of 20%–30%, which is about an order of magnitude larger than that of the regular patch antenna. Recently, it was shown that a half U-slot patch antenna, with half of one of the dimensions of the U-slot patch, maintains similar wide-band behavior. The half-structure was also successfully applied to the U-slot with shorting wall. In this paper, new results on half structures, not previously published, are presented. First, the shorting pin technique is used to reduce the size of the half U-slot patch antenna. By both simulation and experimental studies, it is concluded that the impedance bandwidths, radiation patterns, radiation efficiencies and gains of the half-structures are comparable to the corresponding full structures. Bandwidth of 28.6% and radiation efficiencies exceeding 90% are obtained for the half U-slot patch with shorting pin. Radiation patterns are stable across the matching band. Second, it is shown that a structure obtained from halving the E-shaped patch, which is a derivative of the U-slot patch, also maintains its wide-band behavior.