Powerline Adapters: 3 Simple Checks to Avoid a Dud Buy

What are powerline adapters and how do they work?

Powerline adapters send your broadband signal through your home’s electrical wiring instead of through the air. Your house wiring already reaches every room, so powerline adapters put it to a second use as a network cable. No drilling, no trailing Ethernet across the landing.

They come in pairs. One plugs into a wall socket next to your router and connects to it with an Ethernet cable. The other plugs in wherever you need a connection, such as a home office or a games room, and gives you an Ethernet port.

Some kits also put a WiFi hotspot in the second unit, so you can drop it into the far room and get a fresh wireless signal there. Ethernet only kits suit anything that likes a cable, such as a desktop, a smart TV or a games console. Moving those devices off WiFi also frees up the wireless signal for phones and laptops.

The appeal is simple. If WiFi struggles to reach the back bedroom, a wired connection through the mains can beat it. Whether powerline adapters actually work for you depends on the wiring, which is the bit nobody can see.

Are powerline adapters faster than a WiFi extender?

Often more stable, sometimes faster, and never as fast as the number on the box. A WiFi extender has to receive your signal and then rebroadcast it, which takes a bite out of your speed. Powerline adapters avoid that by using a wire, so a good pair can hold a steadier connection for streaming or gaming.

The box speed is a lab figure, measured on ideal wiring that no real house has. As a rule of thumb, expect a large gap between the rating and what you actually get, often less than half of it, and sometimes a good deal less again on older wiring. A pair rated at 600Mbps will not deliver 600Mbps, and neither will a 2,000Mbps pair. Your own wiring decides the outcome, which is why nobody can quote you a figure in advance.

Consistency is the other selling point. WiFi speeds swing with walls, distance and your neighbours’ networks, while a wire through the mains tends to be steadier once it is working. That matters more for video calls and gaming than a big headline number does.

If your problem is a weak WiFi signal across the house, mesh WiFi might be the better answer, and our guide to mesh WiFi versus range extenders compares the options. If it is one stubborn room, powerline adapters are worth a look.

When do powerline adapters not work well?

Powerline adapters are fussy about electrics. These are the usual culprits when the result disappoints:

• Different circuits: adapters work best when both plug into sockets on the same circuit. Older homes with several circuits may see a weak link or none at all.
• Extension leads and surge protectors: plug adapters straight into a wall socket, because extension leads can cut the signal.
• Electrical noise: chargers, fridges and dimmer switches can interfere with the signal.
• Old or unusual wiring: the older and more patched the wiring, the more variable the result.
• Outbuildings: a garden office often sits on a separate supply, so powerline adapters may not reach it.

The good news is that the test is cheap. If you can, buy from a shop with an easy returns policy, plug them in and run a speed test in the room you care about.

What speed do you actually need from powerline adapters?

Less than the box suggests. Powerline adapters cannot make your broadband faster than the line coming into your home. If your broadband delivers 70Mbps, a pair that comfortably clears that in real use is already enough.

So buy for your broadband, not for the biggest number on the packaging. Check what your line can deliver first. Ofcom’s broadband checker shows the speeds available at your address, which is the ceiling for whatever powerline adapters can pass on.

It also helps to rule out simpler fixes first. Moving the router to a better spot costs nothing, and our guide to router placement shows how. Our guide to boosting home WiFi covers the rest.

Three quick checks before you buy powerline adapters

1. Check your circuits. If the two rooms sit on different circuits, for example an upstairs and downstairs consumer unit, powerline adapters may struggle.
2. Match the kit to your broadband speed, and choose a pair that plugs straight into the wall without passing through an extension lead.
3. Check the returns policy, then test in the room you care about with a speed test.

Poor WiFi is one of those things households put up with for years, because doing nothing costs nothing until you count the buffering. If the real culprit is your broadband deal rather than your wiring, a comparison takes a few minutes and shows what is available at your address.

Compare broadband deals

Frequently asked questions about powerline adapters

Checked 29 September 2026.