You can now place some Microsoft Teams calls with the confidence they'll be reasonably secure. The Vergenotes Microsoft has made end-to-end encryption widely available for one-on-one calls after publicly testing the feature since October. If your company's IT administrator enables E2EE and both ends of the call choose to use the feature, it should be that much harder for intruders to spy on conversations.
Microsoft cautioned that you'll lose several significant features if you use the stricter encryption, including recording, call transfers, expanding to group calls and live captions. You'll have to disable E2EE to regain those options.
This could still be important. While Teams was already using encryption both in transit and at rest, it still offered a window for decrypting content so that approved services could honor data retention records. End-to-end encryption prevents anyone beyond the intended recipients from decrypting call data — that's great for privacy, but not so hot for companies, governments and law enforcement agencies that want backdoors. It won't be surprising if authorities bristle at Microsoft's move.