When power goes out in half of your house, it feels strange. One side of the home works normally. The other side is completely dead.
It’s confusing because it doesn’t behave like a normal outage. If the power were fully out, nothing would work. If it were a simple breaker issue, you would expect only one room to be affected. But half the house?
The short truth is this: most half-house power losses involve one leg of the electrical service. This is usually not random and not limited to a single outlet. It often points to an issue in the electrical panel, the main breaker, or the incoming utility service.
In this guide, we’ll explain why this happens, what you can safely check, and when it’s time to call a professional.
Quick Takeaways
• If power is out in half of a house, one leg of the split-phase electrical service may be disconnected.
• Most homes receive two 120-volt legs from the utility, which supply separate groups of circuits.
• A failed double-pole breaker or loose panel connection can interrupt one side of power.
• Utility transformer or service line problems can also cause partial power loss.
• Diagnosing half-house outages requires electrical panel testing and service-level inspection.
The Short Answer: Why Power Goes Out in Half of a House
Most homes run on 120/240-volt split-phase power. The electrical panel receives two hot legs from the utility. If one leg fails, half the circuits lose power while the other half continues working.
This typically affects multiple rooms, not just one outlet. The problem may originate inside the panel, at the main breaker, or outside at the utility connection.
How a Home’s Electrical System Delivers Power
Understanding the basics makes this issue much clearer.
Residential homes in the U.S. use 120/240-volt split-phase service. Two hot legs enter the electrical panel from the utility transformer. Each leg carries 120 volts. When combined, they provide 240 volts for large appliances.
Inside the panel, breakers distribute power across both legs. Some breakers connect to one leg for 120V circuits like lighting and outlets. Double-pole breakers connect to both legs for 240V appliances like HVAC systems, dryers, or ovens.
If one leg drops out, everything connected to that leg loses power. The other leg continues operating normally. That’s why part of the home works and part doesn’t.
This is very different from a simple outlet issue. A single outlet problem affects one circuit. A split-phase failure affects multiple circuits tied to the same leg.
Common Causes of Power Out in Half of House
Several distinct failures can cause partial power loss.
1. Tripped or Failed Double-Pole Breaker
The main breaker or a large double-pole breaker can disengage on one side.
Sometimes the breaker appears on but is internally failed. One leg may remain active while the other disconnects. Cycling the breaker fully off and back on can help confirm whether it has tripped.
2. Loose Connection Inside the Electrical Panel
Loose or overheated connections inside the electrical panel can interrupt one leg of power.
A loosened hot conductor or neutral wire can cause imbalance. Signs of panel stress may include warmth, discoloration, or flickering lights.
This type of issue requires professional diagnosis.
3. Utility Company Service Issue
Sometimes the issue is outside the home.
Transformer imbalance, a dropped service leg, or storm damage can interrupt one side of the incoming power. If neighbors report similar issues, the utility company may need to respond.
4. Damaged Service Cable or Meter Connection
The service cable running from the utility to your home can become damaged.
Corrosion, mechanical stress, or weather exposure can weaken connections. A compromised meter base connection can also cause one leg to fail.
5. Burned Neutral Connection
A burned or loose neutral can create unstable voltage.
This often causes flickering or dimming lights on one side of the house. It can also damage 240V appliances because voltage becomes unbalanced. This condition requires immediate professional evaluation.
Safe Checks You Can Perform
There are a few safe steps homeowners can take before scheduling service.
- Check the main breaker in the electrical panel.
- Reset it fully by switching it completely off and then back on.
- Look for visibly tripped breakers inside the panel.
- Ask neighbors if they are experiencing similar issues.
Do not remove the panel cover.
Do not touch service wires or attempt internal repairs.
If resetting breakers does not restore power, further inspection should be handled by a licensed electrician.
Signs This Is an Emergency
Partial power loss is not always urgent, but certain symptoms increase concern.
Watch for:
- Burning smell from the electrical panel
- Buzzing or crackling sounds
- Flickering or dimming lights on one side of the house
- 240V appliances not operating correctly
- Breakers that repeatedly trip
These signs indicate instability and require prompt professional attention.
Why This Is Not a Simple Outlet Issue
Outlet problems are localized. They affect one room or one section of wiring.
When power is out in half of the house, the issue points to a service-level imbalance. This involves the electrical panel, incoming power, or the utility connection.
Treating this like a simple outlet repair can delay proper diagnosis. Service-level issues require panel inspection and voltage testing.
FAQs About Power Out in Half of House
Why is half my house without power but the other half works?
Most homes use split-phase service with two hot legs. If one leg fails, circuits connected to that side lose power while the other side continues working.
Can a breaker cause half the house to lose power?
Yes. A tripped or internally failed double-pole breaker can disconnect one leg of power, causing partial outages.
Is this a utility company problem?
It can be. If neighbors have the same issue, or resetting breakers does not restore power, the utility may have a dropped service line. A transformer may also have a problem.
Is it dangerous if half my house loses power?
It depends on symptoms. If you notice flickering lights, burning smells, or unstable appliances, the issue should be addressed quickly.
Should I call an electrician or the power company first?
If multiple homes are affected, call the utility. If only your home is affected, contact a licensed electrician to inspect the panel and service connections.
Schedule Electrical Troubleshooting Today
If power is out in half of your house, clear diagnosis matters.
Right Touch Electrical provides fast, safety-first troubleshooting by licensed electricians across Houston, TX and nearby communities. We identify the cause, explain your options, and restore stable power without unnecessary delays.
Every job is handled with attention to detail and professionalism—delivering quality with a master’s touch.
