---
title: "What Is Three-prong outlet? Electrical Glossary"
description: "A three-prong outlet is a grounded receptacle with a round ground slot beside the two flat slots. Plain-English glossary from Daniel Electric in Southlake, TX."
url: https://danielelectric.multisites.ai/glossary/three-prong-outlet
publisher: Daniel Electric
phone: +1-817-481-8606
quote: https://danielelectric.multisites.ai/contact
---

Wiring and circuits

# Three-prong outlet

A three-prong outlet is a grounded receptacle with a round ground slot beside the two flat slots.

The round slot connects to the building's grounding path, so a fault in an appliance can flow to ground and trip the breaker. OSHA says receptacles with grounding contacts shall have those contacts effectively grounded. It also says grounding-type receptacles are used where a grounding means exists in the box.

A three-prong face on an old outlet does not prove a ground is present. A tester or a licensed electrician must confirm it. See [ungrounded outlet](https://danielelectric.multisites.ai/glossary/ungrounded-outlet) for older homes. The ground wire is the [equipment grounding conductor](https://danielelectric.multisites.ai/glossary/equipment-grounding-conductor). See the [home electrical safety checklist](https://danielelectric.multisites.ai/guides/home-electrical-safety-checklist).

[Daniel Electric can helpResidential electrician](https://danielelectric.multisites.ai/electrician)

## Related terms

-   [Ungrounded outlet](https://danielelectric.multisites.ai/glossary/ungrounded-outlet)
-   [Receptacle](https://danielelectric.multisites.ai/glossary/receptacle)
-   [Equipment grounding conductor](https://danielelectric.multisites.ai/glossary/equipment-grounding-conductor)
-   [GFCI](https://danielelectric.multisites.ai/glossary/gfci)

## Sources

1.  [OSHA: 1910.304 Wiring design and protection](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.304)
2.  [OSHA: 1910.304 Wiring design and protection](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.304)

TECL #21005 · Family owned since 1988

## Need an electrician in Southlake?

Call and tell us what is going on. A photo of the panel label or the problem helps us come prepared. Quotes on new installations are free.

[Call (817) 481-8606](tel:+1-817-481-8606)[Get a quote](https://danielelectric.multisites.ai/contact)

![A Daniel Electric bucket lift raised to a parking lot light pole](https://danielelectric.multisites.ai/_astro/bucket-at-light-pole.BSVZ9eST_1Dp6XR.webp)