The comedy's new run - originally planned to air for just 13 weeks - will now run to 16 episodes, Deadline reports.
Whitney was first scheduled to be paired with Community on Friday nights at 8/7c, but was later shifted to a Wednesday night slot.
Season two currently airs alongside freshman sitcom Guys with Kids. The show returned to NBC on November 14 with 4.22m viewers - the latest episode attracted 3.77m on December 12.
Whitney will return to the network following a break for Christmas on January 2. In the UK, the series airs on Comedy Central.
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Watch a clip from Whitney below: