In a post in The Telegraph, Antigone Davis, Meta's head of safety, attributes the delay to concerns about user safety.
"We are taking our time to get this right and we don't plan to finish the global rollout of end-to-end encryption by default across all our messaging services until sometime in 2023," Antigone Davis wrote in The Telegraph.
"As a company that connects billions of people around the world and has built industry-leading technology, we're determined to protect people's private communications and keep people safe online," added.
With E2EE only the sender and recipient will see their conversations, the firm wants to ensure that this does not interfere with the platform's ability to help stop criminal activity.
Facebook had first started rolling out encryption to its Messenger service back in 2016, but it only works when users use the Secret Conversation feature on the service.
Earlier this year, Meta said that default E2EE would become available on Instagram and Messenger "sometime in 2022 at the earliest."
Facebook has taken criticism over the years for being slow to implement end-to-end encryption by default on all of its platforms.
In addition, Meta is also planning to unify the infrastructure behind the three messaging platforms -- Messenger, WhatsApp and Instagram Direct.