Is It Safe To Plug A Three Prong Plug Into A Two Prong Outlet?

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Though it's far less of an issue today than it was in years past, it's still possible that you have (on at least one occasion) found yourself holding a three pronged electrical plug while looking at a two pronged electrical outlet. If that is the case, you've likely wondered whether or not it was safe to try and plug the three-pronged head in the outlet anyway.

The answer to that question is actually a little bit complicated, though we'd note that two and three prong outlets provide very different functions. The primary difference is that the third pin provides a grounding function that can prevent dangerous electrical surges to the plugged-in device. We should also point out an obvious fact that it's physically impossible to plug a three prong plug directly into an outlet designed for two without altering the plug. That would tend to involve removing the grounding pin, which is dangerous for the same reasons already stated, among others.

You can, of course, bypass the issue by using a two prong to three prong electrical outlet adapter, which you should be able to purchase from most any hardware or home improvement store. They're even selling them on Amazon these days at less than $8 for a four pack. It should, however, be noted that using a plug adapter can be dangerous in and of itself, as most adapters also leave the device ungrounded.

You will not face the same issue using a two pronged plug in a three prong outlet. That fact may leave some wondering why that third grounding pin is such an important feature for certain types of electrical devices. 

That third pin is designed to ground the electrical flow running through the cord to the device its powering. In essence, the grounding feature operates as an additional path for electrical current to flow, re-routing excess power into the ground rather than into the device. The feature is most commonly used with larger appliances like refrigerators, ovens, and microwaves, among others. Grounding is an important safety measure, in that any excess current could overload a device's electrical circuits, resulting in dangerous electrical shocks, damage to appliances' electrical systems, and potentially even fires. 

While a two-prong to three-prong adapter features a hole for the grounding pin of a three-prong plug, they generally do not provide any grounding functionality. Rather, they serve largely to provide power to the two primary pins on the plug, thus leaving devices open to the dangers of electrical overload. You might consider shelling out a few extra bucks to replace any two prong outlets in your home with three prong models, rather than utilizing an adapter, in the long run.