To call one person in Microsoft Teams, open your chat with them and select Video call or Audio call in the upper-right corner. The same basic route works on desktop and mobile. If those controls are missing, the likely cause is policy, account context or the type of person you are trying to call.
Before you call
You need to be signed into the intended Teams account. Your organisation must also allow private calling. Microsoft documents Make private calls in the Teams calling policy as the switch that controls Teams calling capabilities for a user.
A normal Teams-to-Teams audio or video call does not require a phone number. Calling a landline or mobile number is different: that is public switched telephone network calling and depends on Teams Phone configuration, licensing and dialling policy.
Start a call on desktop or web
- Open Chat in Teams.
- Open an existing one-to-one chat, or select New message and choose the person.
- Select Video call or Audio call in the upper-right corner.
- Check the microphone, speaker and camera controls when the call opens.
If you cannot find the person, confirm that you are in the correct organisation. External access and guest access are separate identity routes, and an administrator can restrict them.
Start a call on mobile
- Open the Teams app and select Chat.
- Open the person's chat or start a new message.
- Tap Video call or Audio call at the top of the conversation.
- Allow microphone or camera access if the operating system asks.
Mobile layouts change with screen size and app releases, but the call controls remain attached to the chat with that person.
Answer or decline a call
An incoming Teams notification lets you accept with audio, accept with video or decline. On mobile, tap the incoming-call notification and choose the available answer control.
If calls never appear, check operating-system notification permissions, Teams notification settings and quiet or focus modes. A call can also be routed or suppressed by organisational calling policy.
Fix a missing call button
Work through these checks in order:
- Confirm that chat works with the same person.
- Check that both people are signed into the expected accounts and organisations.
- Try the Teams desktop or web client to separate an account problem from a mobile permission problem.
- Ask the Teams administrator whether Make private calls is enabled for your effective calling policy.
- If the other person is external, ask the administrator to check external-access and federation settings for both organisations.
- Sign out and back in after a policy or account change. Policy changes are not always immediate.
Do not buy Teams Phone simply because the audio-call button is missing from an internal chat. Teams Phone serves telephone-network calling scenarios; it is not the normal fix for a disabled Teams-to-Teams call.
A quick pre-call check
Open Settings and more > Settings > Devices in desktop Teams to select the correct speaker, microphone and camera. Run the available test-call option if your organisation exposes it. A test call checks your device path, not the quality of the other person's connection or the meeting itself.
For sensitive conversations, remember that end-to-end encryption for one-to-one Teams calls is controlled by Teams policy and has feature trade-offs. Do not claim a call is end-to-end encrypted unless the feature is enabled and both participants see the expected indicator.
What this proves
Completing these steps proves that the selected accounts can place and receive a Teams call on the tested clients. It does not prove that telephone calling is configured, that every external domain is allowed, or that call quality will be stable on another network.
For practical Teams policy and troubleshooting guidance, join the SharePoint & Teams Admins Space.