This article explains what a master socket is, the different types available, and how to arrange for one to be moved, replaced or installed.
What is a master socket?
Your master socket is the point where the external phone line enters your premises. It is a white plastic box built into the wall, usually in the hallway or near the front entrance. It is larger than any other phone socket and provides the strongest broadband signal.
All other sockets in your premises connect to the master socket through extension wiring. This wiring is not designed to carry broadband signals reliably and can become damaged over time, so for the best performance always connect your router to the master socket.
Your master socket can also be used to identify faults with your internal wiring, especially if it has a test socket behind the faceplate.
What type of master socket do I have?
There are two types:
Standard master socket: has one port on the front. You will need a microfilter to separate your phone and broadband signals, connected to every socket in use.
Pre-filtered master socket: has two ports on the front. Your phone and broadband signals are already separated, so you do not need microfilters.
Can my master socket be moved or replaced?
If you need to move your master socket to a more convenient location, or it is damaged and needs replacing, an engineer visit can be arranged. There is a charge of up to £120 to move or replace a master socket. If Openreach assistance is required, this charge will increase.
Can I have a new master socket installed?
If you do not currently have a master socket, one can be installed. There is a £65 engineer charge for installation. If Openreach assistance is required, this increases to £120.
I cannot find my master socket
Not all properties have a master socket. Some have a junction box instead: a small metal or plastic box that connects to a single phone socket and has a non-removable faceplate. If your premises has a junction box, it is unlikely you have a master socket. One can be installed if needed, as covered in the section above.