After falling 7% in November, the number of South Island guest nights bounced back 7.2% in December, leading to an overall increase in the national tally.
Statistics NZ said Otago was the "main contributor" to the strong result in the South Island.
The region recorded 492,000 guest nights, up almost 5% on the same month the previous year. The figure for November last year was 330,000.
Total New Zealand guest nights were up 3.1%, recovering from a 2.7% fall in November, Statistics NZ said.
North Island guest nights rose 0.5%. International guest nights rose 6% while domestic guest nights were almost steady, up 0.6%.
Seasonally adjusted, foreign visitors accounted for just more than 1 million guest nights in December, compared with 1.6 million domestic guest nights.
The Accommodation Survey records guests staying in hotels, motels, backpacker accommodation, and holiday parks in New Zealand each month.
Guest nights rose for all types of accommodation, except for backpackers.
