Nov 1 (Reuters) - Insurance provider Aflac on Wednesday reported third-quarter profit above estimates, helped by higher premium revenue from its U.S. unit and strong gains on its investments.

Its U.S. unit earned net premiums of $1.4 billion for the quarter, up 3.2% from year earlier.

Adjusted earnings for the quarter rose 20% to $1.1 billion.

Net earnings totaled $1.6 billion, compared with $1.8 billion a year earlier.

On an adjusted basis, Aflac earned $1.84 per share in the quarter, compared with analysts' estimates of $1.48 per share, according to LSEG data.

Aflac shares rose about 1.2% to $80 in extended trading. (Reporting by Pratik Jain in Bengaluru; Editing by Anil D'Silva)