Nashville's tallest under construction, the 542', 40 story Four Seasons Residences, would be the second tallest when built.
The tallest proposed is the Paramount Tower which will be a ceiling shattering 750' tall, 65 story residential tower.
The Paramount is asking to locate on a small city park, so there is reluctance by some to grant approval. I think the issue may be settled one way or the other soon.
The current tallest is the 617' (including 90' spires), 32 story AT&T Building aka; The Batman Building!