When you go to your router web interface just use the admin credentials below. You also try other password if the first one is not working on your modem.

Username: adminpldt
Password: 1234567890 or 0123456789

PLDT user account

Username: admin
Password: 1234


Fibr and Home Bro accounts

PLDT Fibr Huawei

User: telecomadmin
Password: admintelecom

Other account:
Username: admin
Password: admin

PLDT Home Bro Ultera

Access thru IP address https://192.168.15.1 use: User: homebro
Password: homebro

Model: Ultera OT-350 4G/LTE(Color White)
Type IP address 192.168.15.1 use:

Username: homeultera
Password: homeultera

For Home Bro Ultera Black router try:
Username: voip

Password: 1234

This will mostly work on all PLDT myDSL issued modem like Zyxel, Speedsurf, Kasda, Huawei and other brands catered by the company. Login credentials also works on PLDT Home DSL and Fibr router page.

If you can't access using the default router IP (192.168.1.1) follow steps below:

Go to command prompt (Windows) or just press Windows + R on your keyboard
Type 'cmd', then type 'ipconfig /all'.
Look at your LAN adapter (Wi-Fi or Ethernet whichever is connected to the PLDT router).
Take note the 'Default Gateway' numeric IP address, something like 192.168.X.X.
Go to your web browser and input the Default Gateway IP in step no. 4. and hit Enter.
It should take you to the login page, input the PLDT admin password above.

Tip:
In case all of the credentials given above does not work on your PLDT router you can always call PLDT hotline to ask for assistance regarding your problem.