Why it matters

SIP domains and credential lists define how SIP users authenticate and connect through a provider account.

Key Concepts

SIP Domains: The Domains tab lists SIP domains for the selected provider account, including name, domain, created date, and actions.

Credential Lists: Credential Lists store SIP credentials used by SIP users and related voice infrastructure.

Credential Attachments: Credential Attachments link SIP domains to credential lists.

Open Settings > Accounts.
Open the provider account you want to manage.
Select Domains to review SIP domains or create a SIP domain.
Select Credential Lists to review or create credential lists.
Select Credential Attachments to link SIP domains to credential lists.
Confirm that the domain and credential list relationship is correct before adding SIP users.
Test any SIP user or phone that depends on the changed setup.

SIP domains in Accounts are different from Settings > Domains for links and email.
Create the SIP domain and credential list before attaching them.
Avoid duplicate or unclear credential list names.
Coordinate credential changes with phone and extension testing.

Issue	Possible Cause	Fix
No SIP Domains Found	The provider account does not have a SIP domain yet.	Create a SIP domain from the Domains tab if the account needs SIP users.
Cannot create a credential attachment	A SIP domain or credential list may be missing.	Create both required resources before creating the attachment.
SIP users cannot connect	The SIP domain may not be linked to the correct credential list.	Review Credential Attachments and verify the SIP user's credential list.