Total guest nights in May rose 1.6% to 2.54million from May last year when they grew 7.3%, Statistics New Zealand said.
The country's accommodation sector is booming, helped by record levels of tourism and migration.
The growth in total guest nights in May was driven by more domestic guest nights spent in accommodation across New Zealand, and more international guest nights in the South Island.
Together, these increases offset a fall in international guest nights in the North Island.
"This month's increase builds on the stronger guest night growth we saw last May," Stats NZ accommodation statistics manager Melissa McKenzie said.
"May is typically one of the quieter months for accommodation providers, as we head into cooler months."
"This contrasts with the summer peak, when nearly twice as many guest nights are spent in commercial accommodation."
Guest nights in the South Island increased 4.1% to 971,000, while the North Island continued to record the highest number of guest nights, edging up 0.2% to 1.57million.
Domestic guest stays increased 2.5% to 1.49million while international guest nights lifted 0.4% to 1.05million.
Hotels were the biggest beneficiary of the increase, with stays up 3.6% to 1.05million, while motel stays lifted 1.3% to 801,000 and holiday park nights were up 1.7% to 361,000.
Backpacker nights dropped for a fifth straight month, down 3.7% to 333,000.
The data does not include hosted and private accommodation.
The occupancy rate across accommodation types lifted to 37.5% in May from 37% a year earlier.
