A company spokesperson said that users between the ages of 13 and 15 in some European Union countries will need permission from a parent or guardian to use some of the platform's features.
WhatsApp is raising the minimum age of its users in Europe from 13 to 16 to comply with the new data protection rules.
Under the new legislation, which comes into effect from 25 May, people have the right to get any of their personal data stored by a company erased, and to prevent third parties from collecting information on children for marketing purposes.
The laws will govern how a company can collect data from you, ensure that any data it stores is securely protected, and will give you the right to access that data at any point.
WhatsApp's parent company, Facebook, isn't excluding under 16-year-old users.
The uneven responses among the companies are frustrating privacy advocates, who argue that the arrival of GDPR offers an opportunity for fundamental change - beyond just a series of new explanations and consent boxes that users are asked to check.
It is the fifth most popular social network among that age group after Facebook, Snapchat, Instagram and YouTube.
Up until now you had to be at least 13 to use the mobile messaging app WhatsApp. 13 remains the age limit in non-European regions.
WhatsApp have also stressed that nobody, including WhatsApp or Facebook can read messages sent via end-to-end encryption on the messaging service.
Following weeks of controversy regarding what data Facebook collects and how it's used, the company is jacking up efforts to make users feel more comfortable. It will soon become available for Android and iPhone app users. We believe you should know the types of data you share with us and how we use it.
Facebook has also come under pressure from regulators and lawmakers around the world since disclosing last month that the personal information of 87 million users ended up in the hands of political consultancy Cambridge Analytica.