The reactions of BrH2B·SMe2 or Br2HB·SMe2 with a variety of primary, secondary, tertiary and chelating phosphines affords a range of boronium salts of the form [HXB(PR3)2]Br (X = H, Br), e.g., the ferrocenophane shown. The equilibrium between such species and the neutral haloborane adducts HXBr(PR3) is discussed.