A dead lower outlet with a live upper one is rarely a fault. A switched half-hot receptacle is created deliberately by snapping off a small brass tab between the two hot terminals, which separates the halves so a wall switch can control one while the other stays energized. Recognizing the pattern turns a mystery into a five minute decision.
The tab that makes the two halves one device
Look at the side of a standard receptacle and you will see two brass screws joined by a thin metal link, and two silver screws joined the same way. Those links tie the upper and lower outlets together so a single supply feeds both. Break the brass link with pliers and the two hot terminals become independent, letting one be fed from a switch leg and the other from the constant supply. The silver link on the neutral side usually stays intact, since both halves share a return. Breaking the wrong one produces a half of an outlet that is hot with no neutral, which is a genuine hazard.
Why builders wired rooms this way
Bedrooms and living rooms often need a lighting outlet controlled from the door, and a switched receptacle satisfies that requirement without installing a ceiling fixture. A table lamp plugged into the switched half turns on with the wall switch while a clock or a charger in the other half runs continuously. The convention is common enough that a dead outlet in a bedroom should prompt you to flip every switch in the room before you reach for a screwdriver. Whether the top or the bottom is switched varies by installer and by era.
Identifying the wiring in the box
With the power off, pull the device and look at what lands on the brass side. A half-hot arrangement usually shows two hot conductors, often one black and one red from a three-conductor cable, with the tab between the brass screws missing. The neutral side will typically have a single white conductor or a pigtail from a bundle, with its tab intact. If you find a broken tab on the silver side instead, stop and investigate, because separated neutrals on one device generally indicate a multiwire arrangement or a wiring error that deserves a closer look.
Converting a switched outlet to always on
If you would rather have both halves live all the time, the tidy approach is to connect both hot conductors to the constant supply with a pigtail, cap the now unused switch leg safely, and install a new receptacle with its tab intact. Do not simply twist the two hot conductors together at the device and leave the switch in the circuit, because that back-feeds the switch and leaves an energized conductor that behaves unpredictably. The switch itself should be addressed too: either repurpose it or replace it with a blank plate after making the conductors safe in the box.
Where the pattern causes real confusion
Three situations catch people out. A switched half on a circuit with a tripped upstream ground-fault device looks identical to a broken tab. A smart plug installed in a switched half loses power whenever someone flips the wall switch, which produces intermittent home automation failures nobody can reproduce. And a half-hot receptacle in a room where the switch was covered by furniture can go undiscovered for years. Before pulling a device apart, flip switches, check ground-fault devices, and test both halves with a meter rather than a lamp.
What to check before you act
- Flip every switch in the room and retest both halves before opening anything.
- Check upstream ground-fault devices and the breaker for that circuit.
- With power off, look for a missing brass tab and a second hot conductor.
- Never leave a broken tab on the neutral side without understanding why it is there.
Common questions
Can I put the tab back once it is broken?
No. The link is not replaceable, so restoring a shared feed means installing a new receptacle and pigtailing the hot conductors.
Is a half-hot outlet safe to leave as is?
Yes, when wired correctly it is a normal and permitted arrangement. Label the switched half if the behavior confuses people in the household.
The practical takeaway
Treat a dead half as a design choice until proven otherwise. Work the switches and the protective devices first, then confirm the broken tab in the box. If you convert the outlet to constant power, deal with the abandoned switch leg properly instead of leaving it connected to nothing useful.
References and further reading
- OSHA 1910.304: branch circuit wiring design and identification requirements
- CPSC: home electrical safety guidance for outlets and switches
- NFPA: electrical safety resources for residential wiring
Numerical scenarios are illustrative unless identified otherwise. Follow the exact product instructions; component ratings and local installation requirements can differ.
