WhatsApp users will not be able to read or send messages after May 15 unless they accept the app’s updated terms and conditions.
The messaging service, which is owned by Facebook, will be displaying a banner alert in the coming weeks.
Users who do not accept the new terms will still be able to receive calls and notifications for a “short time”, but messaging will not be possible.
WhatsApp warned that inactive accounts are generally deleted after 120 days - but there will be a chance to agree after the deadline and have full functionality restored, Wales Online reports.
It comes after a previous attempt earlier in the year was halted amid fears data on the app would be shared more closely with Facebook’s main social network.
"To give you enough time to review changes at your own pace and convenience, we’ve extended the effective date to May 15th,” WhatsApp said.
"If you haven’t accepted by then, WhatsApp will not delete your account."
Earlier this year, the app began sending full-screen notifications to users alerting them they needed to review and agree to new terms of service and privacy policy in order to continue using the platform.
The alerts sparked confusion and concern among some users over possible increased data sharing.
In the days that followed, rival messaging apps saw download numbers increase as some moved away from WhatsApp leading the firm to clarify the nature of the change and delay its rollout.
The platform has reiterated that the update will not allow WhatsApp or Facebook to read or listen to messages sent by users and is focused on policy changes necessary to allow users to message businesses on WhatsApp.
A spokesperson for WhatsApp said: "WhatsApp updated it policy over four years ago to outline how we work with Facebook - and the summary remains the same as what we said at the time.
"Every user will be notified within the chat if the business they are talking to has chosen to use Facebook to manage and store their WhatsApp messages.
"People do not have to message or interact with businesses on WhatsApp if they choose not to do so.
"As has always been the case, users are in control of who they chat with and can still easily block a business on WhatsApp if they want.
"Anyone who hasn’t accepted by that time will need to do so in order to keep using WhatsApp."
