John states that he is writting Revelation while on the island of Patmos. His imprisonment there occurred near the end of his life, in the A.D. 90's. Thus a later date of A.D. 96-97 appears to be the most likely.
The date of John's death is not known. The latest date is A.D. 98.
Encountering the New Testament, Walter A. Elwell / Robert W. Yarbrough, 1998, Baker Books, page 79
A Survey of the New Testament, Third Edition, Robert H. Gundry, 1994, A Survey of the New Testament, Third Edition, Robert H. Gundry, 1994, Zondervan, page 127