Powerline adapters can be very useful home networking solutions, but one crucial question potential users want to know is about speeds. Do they reduce speeds? Or increase speeds? What effect does using powerline adapters have on speeds?
As with a lot of things in networking, it depends in relative terms on what you’re comparing it to before. I’ll assume most people want to know whether using powerline reduces speeds versus using ethernet. And on this, the answer is pretty clear.
Powerline adapters will rarely or never deliver exactly the same speeds as if you were plugged into the router directly with a LAN cable. However, they can at least deliver strong speeds when the wiring is in good condition, and also improve speeds versus using weak Wi-Fi connections at distance from the router.
In other words, it depends on what kind of connection you were using before. But in general terms, powerline connections are slightly to moderately worse than direct ethernet connections, but often better than wireless connections in terms of speeds.
Let’s cover the different scenarios.
Powerline Adapters Rarely Deliver Full Speeds (Versus Ethernet)
Let’s cover the more negative side of things here. It is true that powerline adapters will basically never deliver exactly the same speeds as if you were plugged into the router with a cable direct, instead of sending the signal via the house wiring.
In some cases, with perfect wiring and no interference, you can get close. You might get 90-95% of the speeds of a direct ethernet connection in a best case scenario. You can probably find someone, somewhere who’s also claimed to get 100% of the speeds (I never have myself).
But it’s going to very rare and there’s realistically always going to be some speed loss using a powerline adapter versus plugging into the router direct.
This can be anything from 10% to 50% speed loss or more, depending on conditions and setup.
When I tested this myself, I had about a 30% speed loss using powerline versus ethernet, so I got about 70% of the speeds I got when plugged in direct.
| Test Number | Powerline Speeds | Ethernet Speeds |
|---|---|---|
| 1 | 47Mbps | 69Mbps |
| 2 | 46Mbps | 70Mbps |
| 3 | 48Mbps | 67Mbps |
| 4 | 49Mbps | 64Mbps |
| 5 | 49Mbps | 63Mbps |
| 6 | 48Mbps | 70Mbps |
| 7 | 47Mbps | 67Mbps |
| 8 | 46Mbps | 64Mbps |
| 9 | 49Mbps | 69Mbps |
| 10 | 48Mbps | 68Mbps |
| Average | 47.7Mbps | 67.1Mbps |
Your speeds are going to vary in every case, but in decent conditions with decent wiring, 20-30% speed loss versus direct ethernet is reasonable to expect.
See my post on powerline vs direct ethernet speed for more on this issue, including the tests I did myself on both laptop and console.
Powerline Adapters Can Improve Speeds Relative To Wi-Fi
But let’s also cover the other side of the equation, since on some cases powerline adapters can improve the relative speeds you get versus before.
The most common example of this is when you’re using a very weak Wi-Fi connection further away from the router, with very low speeds and perhaps intermittent signal drop outs.
Using a powerline adapter here can help you bypass Wi-Fi altogether and get on a strong wired connection that delivers much better speeds than what you were getting on wireless.
Therefore it’s all relative and depends on the quality of the connection you’re coming from, what effect powerline adapters have on your speeds.
Other Factors Which Can Affect Speed
Here are some of the things which can affect the speeds you get out of powerline adapters:
- The quality and condition of the powerline adapters being used (stick to newer models from reputable brands. Older ones from the mid 2000s don’t work nearly as well as newer ones).
- The distance between the adapters (close together or far apart).
- The quality of the electrical wiring they are sending data on.
- Whether the two adapters are installed on the same circuit phase or ring. They can often work across different phases/rings as long as they are fed by the same meter, but there is often a drop in performance each time they cross over into a new phase. The linked article goes into full detail about this.
- How busy or congested the home network is when you test it (bandwidth is always shared across a network so the more adapters that are being installed and used, the less bandwidth per device/adapter).
- How close the adapters are to high energy usage electrical equipment, like washers, dryers or electro-motor tools.
- Whether the adapters are plugged directly into wall outlets or into extensions instead. They work far less effectively in extensions/multi-plug power strips.
- If you are using different models of adapter, performance may also suffer, and speeds are always limited to the capability of the slowest adapter being used.
How To Improve Powerline Speeds
If you’re not happy with the speeds you’re getting from powerline adapters, here are some things you can try to improve them:
- Try in different rooms and wall sockets
- Avoid using across phases/circuits.
- Move them away from high power consumption devices.
- Make sure you’re using compatible brands/models and get rid any slower ones that will pull down the speed of the entire network.
- Get faster internet
- Use at quieter times when the network is less congested.
See my post on improving powerline speeds for more on each of these points, plug other tips
