What do I do if I'm experiencing a faint line? 

There can be several reasons why your phone line is faint. It's not necessarily always a fault on the telephone network.

Below are a series of checks you can do to ensure that it's not your own equipment or wiring that is causing the problem. Carrying out these checks thoroughly could mean that you solve the problem yourself - saving your time and reducing frustration. It also means that an engineer doesn't have to come to your home unnecessarily - avoiding you having to wait for a visit.

1. Do you have a cordless telephone? If you have a cordless phone, it may not be fully charged or the batteries may be flat. Please check your product user guide.

2. Does the faintness occur on all calls or a call to one particular number? If the faintness occurs on one particular number, it is likely that the other number has a service problem.

3. Check all your telephones.

  • Check all telephones are on hook.
  • Check all telephone cords including the handset cord are plugged in and secure.

4. Does this happen on all telephones in the house, or just one? Check if the problem only occurs on one telephone, it is unlikely there is a fault with the telephone line, but the telephone itself is likely to be faulty.

5. Unplug all your equipment, if you have an old-style telephone that cannot be unplugged, proceed to step 11 below.

  • Unplug all telephones, faxes, PCs, modems, satellite television digi-boxes, extension leads and adaptors, double adaptors from all your telephone sockets.
  • If you have broadband, don't forget to unplug all micro-filters and your ADSL modem/router from the telephone sockets as well, as these may affect your telephone line.
  • There shouldn't be anything left plugged in to your telephone socket.

6. To test for the fault on equipment, take one working corded (not cordless) telephone and plug into the main socket pictured below. The main socket is usually found where the telephone line comes into the premises. Check for the problem again by using the working phone.

7. If you can make calls at the main socket, your telephone line and extension wiring are likely to be ok, and the problem is likely to be in one of your items of equipment.

  • Plug each piece of equipment that you have previously unplugged back in one at a time.
  • Check for dial tone. The piece of equipment that causes problem may be faulty.
  • Unplug this piece of equipment and keep unplugged. You should refer to any product manual supplied with this, or contact the supplier.

8. If the problem persists at the main socket, we now need to eliminate your own extension wiring as the cause of the problem. If your main socket looks like this socket, with a horizontal bar across the front template:


Carefully unscrew the 2 small screws and the bottom half of the faceplate should pull out. On the right hand side is a test socket. This connects you directly to the telephone line and bypasses any extension wiring you may have.


Plug the corded telephone into the test socket as above. Check for the problem by making test calls from the working telephone. Note if your main socket does not have a horizontal bar across the front and looks like this:


Do not unscrew the face plate. Please proceed to step 11 below.

10. If you can dial out at the test socket it is likely that your internal wiring is faulty. You now have the choice of repairing the wiring yourself or contacting a telephone maintainer, who is likely to charge you unless the wiring is covered by a warranty.

11. If the problem persists at the test socket Try another corded (not cordless) phone into the main test socket to eliminate the first corded phone as being the cause of the problem.

12. If the problem still persists at the test socket it is likely that there is a fault with the telephone line and you will need to report this to your telephone service provider. If this is us, you can identify, fix, report and track faults online at the Repair Centre or contact us.

If you rent your telephone from BT and believe it to be the cause of the fault, please contact our faults department and we will arrange for a new telephone to be delivered to you. You can also buy telephones from us:

Online at the BT Business Shop or please call Business Sales.

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