In this paper, an ultra-wideband (UWB) antenna with a band notched filter is proposed. The transmission range of this antenna covers the FCC unlicensed band from 3.1 to 10.6 GHz with a notch filter from 4.9 to 6.3 GHz to avoid interference with IEEE802.11a system. The notch filter is implemented using a U-shaped slot. To extend the impedance bandwidth of the antenna, an electroband-gap (EBG) structure is used. EBG lattice holes surrounding the radiating patch enhances the impedance bandwidth to be from 3 GHz to 12 GHz with a return loss (S11 < -10 dB). The return loss (S11) for the designed antenna is simulated using HFSS® software package. The antenna design is also fabricated on Rogers RO3006 substrate and measured using Vector Network Analyzer (HP8719ES). The measurement results also confirm that the proposed technique is effective in extending the impedance bandwidth to 12 GHz.