A coated article includes a low-emissivity (low-E) coating. The low-E coating includes at least one infrared (IR) reflecting layer of a material such as silver, gold, or the like, and a dielectric overcoat designed to increase solar heat gain coefficient (SHGC) of the coated article. A dielectric undercoat may also be designed to increase SHGC of the coated article in certain example embodiments. In certain example embodiments, the overcoat and/or undercoat are designed to increase SHGC while also providing for desirably high visible transmission (TY or Tvis) and desirably low normal emittance (En).