Microsoft Teams: Chat With External Users Without Adding Guests

You can chat with external users in Microsoft Teams without adding them as guests by using external access. Start a new chat, enter the person’s full Teams email address, select their external account, and send a message. For work or school contacts in another organization, both organizations must permit the communication.

External access vs. guest access: what changes?

External access, also called federation, lets people communicate while using their existing accounts. Guest access creates a guest identity in your organization’s Microsoft Entra directory. A different email suffix alone does not determine which access method someone has.

External users are not limited to one-on-one conversations, and they can be invited to meetings. Guest access is useful when someone needs ongoing access to a team’s channels and resources. See Microsoft’s external access and guest access comparison.

How to chat with an external Teams user

Use Teams with your work or school account. Button names can differ between interface versions.

1. Open a new conversation. Select Chat, then the compose button labeled New message or New chat.
2. Enter the full email address. Use the address associated with the recipient’s Teams account, rather than searching only by name.
3. Select the correct result. Check the person’s identity and the External label before continuing.
4. Write and send your message. Introduce yourself and explain why you are contacting them. The recipient may need to accept the message request.

To start a group conversation, enter the other participants’ email addresses in the new chat before sending your message. External participants must use Teams or Teams Free. Microsoft’s external chat instructions explain the supported options.

What an administrator needs to enable

A team owner does not automatically have permission to change organization-wide external access. Ask your Teams administrator to check Users > External access in the Teams admin center. Both the organization settings and the policy assigned to your user must allow external communication.

For a restricted allowlist, the administrator selects Allow only specific external domains, chooses Add external domains, enters the partner’s domain, and selects Done. An allowlist blocks domains not listed. The partner organization must also allow communication with yours.

Can you chat with someone using Gmail or a personal account?

Possibly, but adding gmail.com to an organization-domain allowlist does not make every Gmail address reachable. For Teams Free accounts, the administrator must review People in my organization can communicate with unmanaged Teams accounts. A separate option controls whether those accounts can initiate contact.

Use Microsoft’s external access settings guide to check the configuration for the recipient’s account type.

Can an email invitation create a guest account?

Be careful with non-Microsoft 365 contacts, including personal email addresses. Microsoft also documents Chat with people not using Teams (Preview), which can invite someone by email and create or reuse a B2B guest identity, even without adding the person to a team.

That experience is separate from federation. The documentation checked November 1, 2026, labels it Preview, and availability depends on organizational settings. Do not assume that an email-only invitation means no guest account is created. If avoiding guests is essential, ask your administrator to confirm which identity model applies; the External label alone is not sufficient confirmation.

Why can’t you find or message an external user?

• Confirm the account address. Ask the recipient which email they actually use to sign in to Teams.
• Have IT check access. Share the recipient’s address and the exact error so your administrator can investigate restrictions.
• Check the invitation. The recipient may have an unaccepted request or may have blocked the sender.

For unresolved search failures, administrators can run Microsoft’s Teams Federation diagnostic or the Teams Federation and Interoperability connectivity test. The external contact troubleshooting guide lists availability limitations and explains the results.

Recipients can review, accept, or block requests; see Microsoft’s guidance on accepting or blocking external requests. Verify unexpected contacts through a known communication channel before sending sensitive information.