What Are the 4 Types of Electrical Outlets?

PowerMeans Electric
Sep 9
5 min read

Four types of electrical outlets: standard, GFCI, AFCI, and USB combo

When was the last time you thought about your electrical outlets?

If you’re like most people, probably never—unless one stops working or you’re stuck hunting for an open plug when every device in your house needs charging at once. Outlets are the kind of thing we take for granted until they remind us they’re there.

But here’s the truth: not all outlets are the same. Some protect you from electrical shock, others protect your home from fire, and some are just there to make your life more convenient. Choosing the right outlet in the right room isn’t just about code—it’s about keeping your family safe and making your daily life easier.

So, let’s take a walk around the house together. We’ll break down the four most common types of outlets you’ll see in modern homes, plus a few bonus types you might run across in newer builds. By the end, you’ll know exactly which outlets you have, which ones you might need, and when it’s time to call in a pro.

A array of standard three prong outlets — An array of standard three prong outlets.

1. Standard 15A Outlets (Two- or Three-Prong)

If you picture an outlet right now, this is probably the one you see. The 15-amp, 125-volt “standard” outlet is the workhorse of American homes.

Looks like: Two vertical slots and a round hole (the grounding slot) underneath
Found in: Bedrooms, living rooms, hallways
Best for: Lamps, TVs, phone chargers, small appliances

But here’s the catch: not all standard outlets are created equal.

In older homes, you might still see two-prong outlets—those outlets with just two skinny vertical slots and no grounding hole. They were common decades ago, but today they’re a safety red flag. Why? Without that grounding slot, there’s nothing to safely redirect stray electrical current. That means if something goes wrong, your devices (or worse, you) could take the hit.

If your home still has two-prong outlets, it’s time to upgrade. Not only are they unsafe, but many insurance companies won’t cover damage caused by outdated outlets. An electrical inspection can quickly tell you if your wiring and outlets are up to modern standards.

Takeaway: Standard outlets are fine for everyday use in dry spaces, but they shouldn’t be used in bathrooms, kitchens, or anywhere near water.

GFCI outlets installed in a dripping springs residential home.

2. GFCI Outlets (Ground Fault Circuit Interrupter)

Ever notice outlets with “TEST” and “RESET” buttons in the middle? Those are GFCIs, and they’ve saved countless lives.

GFCI stands for Ground Fault Circuit Interrupter, and here’s what it does: if even a tiny bit of electricity tries to take the wrong path (say, through water—or worse, through you), the outlet shuts off in milliseconds. Think of it like a lifeguard for your electrical system.

Required by code in: Bathrooms, kitchens, laundry rooms, garages, outdoors
Looks like: A regular outlet with “TEST” and “RESET” buttons
Best for: Any location where water and electricity might meet

To put it in perspective: a GFCI can shut off electricity in 1/40th of a second. That’s faster than you can blink.

Homeowners sometimes ask: “Do I really need GFCIs everywhere they’re required?” The short answer: yes. The longer answer is in our guide, Do I Need GFCI Outlets?. Or, if you’re curious about outdoor safety in particular, check out 5 Essential Reasons You Need GFCI Outlets for Outdoor Safety.

Takeaway: If you’re renovating a bathroom, installing an outdoor kitchen, or even just plugging in your Christmas lights, GFCIs aren’t optional—they’re lifesaving.

3. AFCI Outlets (Arc Fault Circuit Interrupter)

If GFCIs protect you from shocks, AFCIs protect your house from catching fire.

AFCI stands for Arc Fault Circuit Interrupter. An “arc fault” happens when electricity jumps through damaged wiring, loose connections, or even inside a malfunctioning appliance. You might notice sparks or hear a faint buzzing sound. Left unchecked, arc faults are one of the top causes of house fires.

Here’s where AFCIs step in: the moment they sense dangerous arcing, they shut off power before the sparks can ignite.

Required in: Bedrooms, living rooms, dining rooms, hallways
Looks like: A GFCI, but labeled “AFCI”
Often combined with: GFCI outlets for “dual function” protection

Many homeowners confuse GFCI and AFCI, but here’s an easy way to remember:

GFCI = Guard against water (shock)
AFCI = Attack sparks (fire)

Curious about the codes behind this? You can dive into the National Electrical Code standards for the nitty-gritty details.

Takeaway: If your home was built before the 2000s, you may not have AFCI outlets. Upgrading adds an extra layer of fire prevention.

USB combo outlet installed in a Dripping Springs office.

4. USB Combo Outlets

Now let’s switch gears from safety to convenience.

USB combo outlets are exactly what they sound like: standard three-prong outlets combined with USB-A or USB-C ports. No more fighting over charger blocks or running around the house to find one.

Best for: Bedrooms, home offices, kitchens, bedside tables
Why people love them: Reduce clutter, future-proof your home, make resale more attractive

They aren’t required by code, but they’re one of those small upgrades that make a big difference. Imagine charging your phone, tablet, and laptop in the same spot—without a power strip.

Takeaway: USB outlets don’t keep your house safer, but they definitely make it smarter.

Bonus: Other Outlet Types You Might See

While the “big four” cover most homes, there are a few other outlet types worth mentioning:

20A Outlets (T-slot): For heavy-duty appliances like refrigerators, microwaves, or laundry machines. Look for the sideways T-shaped slot.
Tamper-Resistant Outlets (TR): Required in newer homes. They have a built-in shutter to keep kids from sticking objects inside.
Smart Outlets: Wi-Fi enabled outlets that let you control power from your phone or schedule appliances. Great for coffee makers, sprinklers, or energy monitoring.

These aren’t necessary for every home, but depending on your lifestyle (or if you have kids), they’re worth considering.

🏡 Where Should Each Type Be Installed?

Outlet Type	Best Location
Standard 15A	Bedrooms, hallways, living rooms
GFCI	Kitchens, bathrooms, outdoors, garages
AFCI	Bedrooms, family rooms, dining rooms
USB Combo	Offices, kitchens, bedside tables

For help assessing your outlet layout, we recommend a full electrical inspection—especially in homes built before 2000.

Bonus: Dual Function Outlets

Some newer outlets combine GFCI and AFCI protection in a single device. These dual-function outlets are great for places that need protection from shocks and fires. This is becoming a common standard in new buildings.

Why DIY Outlet Replacement Isn’t Worth It

Sure, you can buy an outlet at the hardware store for a few bucks. But installing it correctly? That’s another story.

Wiring mistakes can:

Create hidden fire hazards
Cause your GFCI or AFCI to fail when you need it most
Lead to code violations that pop up during resale
Leave you uncovered by insurance if something goes wrong

That’s why upgrading outlets is one of those projects best left to licensed electricians.

At PowerMeans Electric, we:

Replace outdated two-prong outlets
Install GFCI, AFCI, USB, and dual-function outlets
Provide whole-home safety inspections
Serve Dripping Springs, Austin, Bee Cave, and the surrounding Central Texas Hill Country