Configuring Yealink T28 SIP phones for 3CX Phone system

IMPORTANT This guide has been tested with firmware version 2.1.12.10. Be aware that different firmware revisions may have different web interface formats and functionality.

  1. Ensure that you have created the extension to use with the phone in 3CX Phone System. Take note of the Extension Number, the Authentication ID, and the Authentication password that you have entered for this extension.
  2. Switch on the phone. The phone will obtain an IP address provided you have a DHCP server installed on your network. To find the IP, press “Menu” button on the phone and navigate to “Status” option.
  3. Assuming that the phone set’s IP is 10.172.0.104, use a web browser to access the phone set’s configuration, using this URL: http://10.172.0.104. The factory default username and password for accessing web configuration on Yealink phones is “admin” and “admin”.
  4. If the phone was used before, from the menu, select the “Upgrade” and click the “Reset” button to restore phone to factory defaults. Ignore this step if the phone is new.
  5. To start configuring the phone you will need to specify the account details. Click on the “Account” tab and the “Account 1” node beneath.
  6. To enable the line, set the “Line Active” field to “On”.
  7. In the “Display Name” field you should enter user name or display name you wish the phone to send when making outbound calls.
  8. Set the “User Name” and “Register Name” to the value you configured in 3CX phone system as “Authentication ID”.
  9. Set the “Password” to the value you configured in 3CX phone system as “Authentication Password”.
  10. In the “SIP Server” field enter the IP Address of the 3CX Server you wish to Register with.
  11. The “Voice Mail” field is optional, yet, you may wish to enter the 3CX Voice Mail extension number.
  12. Leave all other fields in the section with their default settings and click “Confirm”.


  13. Expand the “Codecs” node and set the enabled codec list to contain PCMA, PCMA and G729, then “Confirm” the change.


  14. Your phone is now configured.

Configuring the Yealink DSS Keys

  1. To configure the DSS programmable keys you will need to click on the “Phone” node and click on the “DSS Keys” subnode.
  2. In the “Key Mode” field choose “BLF” option from the drop down list.
  3. In the “Line ID” dropdown select “Line 1”.
  4. Based on the extension number you want to monitor in the “Extension” field enter the extension number you would like to monitor.
  5. To enable quick pickup of the monitored extension in the “Enable Pickup” field choose “Enabled” and in the “PickupNum” field enter your call pickup code. The default for this is *20*.
  6. Repeat steps 2 to 5 for each DSS Key then “Confirm” the changes.

SIP Phone Configuration Guides