The unit, FiberNet, delivers telecommunications services in Florida, Texas and parts of South Central United States.
The unit’s network consisted of about 9,230 route miles at the end of 2015.
Crown Castle owns, operates and leases shared wireless infrastructure, including towers and other structures, in the United States.
A portion of the proceeds will be used to repay about $370 million of FiberNet’s long-term debt, NextEra said.
The deal is expected to add to NextEra’s earnings immediately upon closing, which is likely to occur in the first half of 2017.
UBS Investment Bank is NextEra’s financial adviser and Hogan Lovells its legal counsel.
Reporting by Ismail Shakil in Bengaluru; Editing by Sriraj Kalluvila