The Facebook-owned platform said the figures were a record high number of messages sent on a single day in the firm's 10-year history.
In the UK, more than 900 million messages were sent on December 31 using WhatsApp.
According to the company's own figures, more than 12 billion of the total messages were picture messages.
The communications service, which has more than 1.5 billion active users, was bought by Facebook in 2014 for around 19 billion dollars (£14.5 billion).
It had risen to prominence because of its encryption-based system which means messages cannot be intercepted or seen by others, including the company itself.
Alongside the New Year's Eve data, WhatsApp published figures on the most popular features of the app over the last 12 months.
Text messaging was the most common use of the service, ahead of status updates - which work in the same fashion as Instagram or Snapchat stories as a collection of photos and videos which disappear after 24 hours.
Picture messaging was the third most common feature used, followed by making calls and voice notes.