Why are my outgoing VoIP calls not working?
After configuring an IP phone, SIP adapter, softphone, or any other SIP-compatible device, it can be frustrating to discover that outgoing calls are not working. In most cases, this issue is caused by a configuration problem, a dialing error, or an account-related limitation.
Before requesting technical assistance, several checks can help identify and resolve the problem quickly.
Step 1: Test voicemail access
The first and most important test is to check whether your SIP account is correctly connected.
Dial *98 from your SIP device to access voicemail.
If you cannot hear the voicemail, this usually indicates an issue with the SIP account configuration.
In this case, verify the following:
- SIP username is entered correctly
- SIP password is correct and contains no extra spaces
- SIP server address is accurate
- No spaces appear before or after the username or password
Correct any errors and try dialing *98 again.
Step 2: Check SIP registration status
If voicemail cannot be reached, your SIP account may not be properly registered.
A common cause is network or router restrictions.
Some routers, modems, or Internet service providers block SIP signaling traffic, particularly on port 5060.
To resolve this:
- Ensure port 5060 is open on your router
- Disable SIP ALG if it is enabled on the router
- Restart the router and the SIP device after making changes
Once registration is successful, retry accessing voicemail.
Step 3: Verify balance and dialing format
If dialing *98 works and voicemail audio is clear, your SIP account is correctly registered.
If outgoing calls still fail, check the following:
- Your account has sufficient balance to place the call
- The destination number is dialed correctly
- The international dialing format is used when required
When in doubt, try dialing the number using the full international format:
00 + country code + phone number
Incorrect dialing formats are a frequent cause of failed outgoing calls.
Other points to consider
In some cases, outgoing calls may also be affected by:
- Call restrictions configured on the account
- Country-specific dialing rules
- Firewall rules blocking outgoing RTP or SIP traffic
Reviewing these elements can help isolate more advanced issues.
When to contact support
If outgoing calls still do not work after performing all the checks above, further investigation may be required.
In this situation, opening a support ticket with detailed information about your configuration and test results will help speed up resolution.
Conclusion
Outgoing VoIP call issues are most often linked to SIP configuration errors, registration problems, incorrect dialing formats, or insufficient account balance.
By testing voicemail access, confirming registration status, and verifying dialing rules, most problems can be identified and resolved quickly.