First, your carrier needs to support the technology. Though all the major carriers should already be on board, smaller regional ones may not have completed the necessary steps yet. Apple's web page on Wireless Carrier Support and Features will tell you if your carrier has adopted the encryption by listing "End-to-end encrypted RCS messaging (beta)" as one of its features.

Second, Android users must be running the latest version of Google Messages. Assuming those two conditions are met, iPhone owners will see a new lock icon in their RCS chats as a sign that the end-to-end encryption is working.

To ensure that your RCS messages are encrypted, you'll need to update your iPhone to iOS 26.5. To do that, head to Settings, select General, tap Software Update, and then tap the Update Now button.

Also: 12+ iPhone settings you can change to noticeably improve its battery life (iOS 26 and older)