Why does my circuit have continuity between neutral and earth when nothing is plugged in?
Quick answer
Continuity between neutral and earth when nothing is plugged in is normal on a TN-S or TN-C-S (PME) supply where neutral and earth are bonded at the origin of the installation. On a correctly wired circuit you should see a low resistance reading, typically under 1 ohm, at the consumer unit end. If the reading appears on a socket circuit mid-run with no appliances connected, suspect a wiring fault, crossed conductors, or a damaged neutral conductor touching an earthed enclosure. Have a qualified electrician investigate before using the circuit.
🏠Homeowner view
Finding continuity between the neutral and earth terminals on a circuit can feel alarming, but in most UK homes it is completely expected and is built into how your electricity supply works. Here is what you need to know.
Why it is usually normal
In the vast majority of UK properties, the electricity supply arrives as what is called a TN-C-S or PME (Protective Multiple Earthing) system. Under this arrangement, the neutral and earth conductors are deliberately connected together at one point, which is the main earthing terminal inside your consumer unit or fuse board. Because of this bond, testing between neutral and earth anywhere in the installation will show a low resistance, usually well under 1 ohm. This is by design and is required to make the electrical safety system work properly.
When could it be a problem
Although a reading between neutral and earth is expected at the consumer unit, there are situations where it can point to a fault.
1. If the resistance is very high (several ohms or more) it could mean the neutral is only connected to earth through a fault rather than through the proper bonded path.
2. If you find a solid continuity reading at an individual socket that does not disappear when you remove the socket from the wall and isolate the wiring, there may be a wiring error where neutral and earth conductors have been swapped or have touched inside a back box.
3. If a circuit has been modified by a previous owner or a non-qualified person, incorrect connections can create a false neutral-earth bond mid-circuit, which is a serious fault.
What you can safely check yourself
You can visually inspect accessible socket faceplates for any obvious signs of burning, scorch marks, or loose wires. Do not open anything if you are not confident working near electrical wiring.
When to call an electrician
You should call a qualified electrician if the reading appears only on one specific circuit and not others, if any sockets feel warm to the touch, if RCDs are tripping without an obvious cause, or if you have any doubt at all about the wiring in your home. This type of fault is straightforward for a trained person to trace and fix, but it requires proper test equipment and knowledge of the installation.