Gas line leak
If you smell gas, this page is not your first step. Leave the building and call 911 or your gas utility from outside.
Free to call. We route you to an independent licensed plumber in your area — PlumbLinker does not perform plumbing work.
If you smell gas right now
- Leave immediately. Take everyone and any pets with you. Don't stop to investigate or gather belongings.
- Don't touch any electrical switches — not lights, not appliances, not the garage door. A switch spark can ignite gas. Leave lights as they are.
- Don't use your phone inside the building. Call from outside, well away from the property.
- Don't start a car in an attached garage.
- Call 911 or your gas utility's emergency line from outside. Utilities respond to gas odor calls free of charge, day or night.
- Don't go back in until emergency responders tell you it's safe.
Your gas utility will locate and shut off the supply at no cost — that's their job and they take it seriously. Only once the situation is made safe does a licensed plumber or gas fitter repair the line and restore service. Do not call a plumber instead of the utility.
Signs of a gas leak
- A rotten egg or sulfur smell (mercaptan, added to odorless natural gas)
- A hissing or whistling sound near a gas line or appliance
- Dead or dying vegetation in a line over a buried gas line
- Bubbles in standing water above a buried line
- A gas bill that rises with no change in usage
- Headaches, dizziness, or nausea that improve when you leave the house
- A pilot light that repeatedly goes out
- Orange or yellow burner flames instead of crisp blue
Carbon monoxide is a separate danger
CO is odorless and colorless, and it comes from incomplete combustion — a cracked heat exchanger, a blocked flue, a poorly vented water heater — not from a gas leak as such. You will not smell it.
Symptoms mimic flu: headache, dizziness, nausea, confusion, fatigue. The distinguishing sign is that everyone in the house feels it, and everyone feels better outdoors. If a CO alarm sounds, leave and call 911.
One on each level and one near sleeping areas. They cost around $30 and expire — check the date stamped on the back, because a ten-year-old detector is decorative.
Repair, after it's safe
| Job | Typical cost |
|---|---|
| Leak detection and pressure test | $150–$500 |
| Repair a fitting or joint | $200–$800 |
| Replace a section of gas line | $500–$2,000 |
| Run a new gas line to an appliance | $400–$2,000 |
| Replace buried exterior line | $1,500–$5,000+ |
Gas work almost always requires a permit and inspection, and often a separate gas fitting license from the plumbing license. Confirm the plumber is licensed specifically for gas work in your state — not every plumber is.
Frequently asked questions
What should I do if I smell gas?
Leave the building immediately without touching any electrical switches, and call 911 or your gas utility from outside. Don't investigate, don't use your phone indoors, and don't go back in until responders clear it.
Does the gas company charge to check a leak?
Utilities respond to reported gas odors at no charge, 24 hours a day. They will locate the leak and shut off supply. Repairing your side of the system afterward is your cost, but the emergency response is not.
Can a regular plumber fix a gas line?
Only if licensed for gas work in your state — requirements vary and it's often a separate credential. Ask directly and verify it. This is not an area to take someone's word for.
What's the difference between a gas leak and carbon monoxide?
A gas leak is unburned natural gas escaping, which has an added rotten-egg odor and is an explosion risk. Carbon monoxide is a byproduct of incomplete combustion, is completely odorless, and is a poisoning risk. Both are emergencies; only one gives you warning through smell, which is why CO alarms exist.
Plumbing emergency right now?
One call routes you to an available licensed plumber in your area. Free to call, 24 hours a day.
Call (888) 876-3092PlumbLinker is a referral service. We connect you with independent licensed plumbers — we do not perform plumbing work ourselves.