This may be a surprise to many, but these quotes below are the only references in the New Testament to the antichrist. A careful look reveals that these verses don't talk about a specific Evil Individual or Entity, but rather calls an antichrist anybody (and all) who deny the divine origin of the Christ Spirit and His Message:

"Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time. They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us. But ye have an unction from the Holy One, and ye know all things. I have not written unto you because ye know not the truth, but because ye know it, and that no lie is of the truth. Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son. Whosoever denieth the Son, the same hath not the Father: (but) he that acknowledgeth the Son hath the Father also." - John I (2:18-23)

"Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world. Hereby know ye the Spirit of God: Every spirit that confesseth that Jesus Christ is come in the flesh is of God: And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world." - John I (4:1-3)

"For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist." - John II (1:7)