By Samara Lynn
This post was done in partnership with The Wirecutter, a buyer's guide to the best technology. Read the full article here.
After 5 hours of research and 29 hours of testing with 12 different kits, we found that the best powerline networking adapter for most people is the ZyXEL 1200 Mbps Powerline AV1200 Gigabit Adapter. A powerline networking adapter transmits an Internet signal over your home's electrical wiring, so it is a good way to provide Internet access to a distant part of your house without running additional cables or using a Wi-Fi extender. The ZyXEL model offered the best combination of price, performance, and power efficiency out of all the adapters we tested. Its speed is matched only by adapters costing significantly more, it's easy to set up, and it's the only model we tested that includes a browser-based management interface.
Who this is for
If you already have powerline adapters, especially a last-generation AV2 kit, you probably don't need to upgrade if you're happy with how they're working.
In our high-performance tests, most of these adapters hit data speeds above 100 megabits per second, which is the kind of speed you want for HD video streaming, game streaming from your PC to your TV, and other demanding tasks. In addition, the latest AV2 adapters support MIMO (Multiple Input Multiple Output), a feature designed to improve throughput and coverage. If you're starting from scratch, getting one of the latest-generation kits is a worthwhile investment.
How we tested
We connected one adapter from each kit to a TP-Link Archer C9 AC1900 Wireless Dual Band Gigabit Router. We used two identical Dell Latitude 3550 laptops as testing endpoints—one connected to a LAN port of the router and the other connected to the Ethernet port of the other adapter in each kit.
We ran two types of throughput tests. The first used a default 64KB TCP windows size, and the second used a larger TCP windows size of 1 MB. We also calculated how much slower the signal got as we moved our adapters apart, from the initial test distance (5 feet apart) to the farthest (at opposite ends, and different floors, of a 1,500-square-foot home).
We then streamed the Marvel Super Heroes 2015 game on the Steam platform and timed how long it took between clicking the command to stream and actual play time, after which we tested the adapters' power-saving modes by using a Floureon TS-836A power meter and then ran a third test for adapters with passthrough outlets. Finally, when moving the second adapter to a new outlet, we checked to ensure that the second adapter paired up right away with its twin, no matter the distance.
The ZyXEL 1200 Mbps Powerline AV1200 Gigabit Adapter (PLA5405) wasn't the fastest in every test, but it has the best combination of price, performance, and power efficiency. The only two adapters that consistently beat it in our benchmarks are either more expensive or based on a totally different powerline networking standard. Plus, ZyXEL has a two-year parts-and-labor warranty and both Web and phone support.
Each PLA5405 has a Gigabit Ethernet port, a combination reset and encryption button on its bottom side, and three LEDs for power, powerline, and Ethernet connection status. The PLA5405 kit comes with two adapters and two 4-foot Ethernet cables. The adapters are compact, measuring 1.06 by 3.54 by 2.36 inches. Unlike many powerline kits, the ZyXEL adapters are small enough that they don't block a duplex outlet's top socket.
Our pick is a HomePlug AV2-compliant adapter, so it's compatible with a huge array of powerline networking kits from many vendors. It also has a power-saving mode, but it's already so power-efficient that the mode doesn't make a significant difference.
If the ZyXEL is out of stock or too expensive, or you want a powerline adapter with a built-in AC passthrough outlet, the Netgear Powerline 1200 + Extra Outlet (PLP1200-100PAS) kit is the best adapter with a passthrough outlet we tested, averaging 111 Mbps. The Trendnet Powerline 1200 AV2 (TPL-421E2K) bested it in high-throughput performance, but the Netgear outperformed the Trendnet in the rest of our tests.
It's one of the largest and longest adapters we tested, though, and its factory-reset and encryption buttons are on the bottom of the device instead of the front. Also, while we could still connect a surge protector into a top socket with the PLP1200 plugged into the bottom socket, it's a tight fit, so larger plugs might not work.
The ZyXEL 1200 Mbps Powerline Gigabit Ethernet Adapter (PLA5405) is the best powerline adapter for most people because of its great performance, good range, easy setup, low power consumption, color-coded LEDs, and useful management utility. If you want a good powerline adapter with built-in passthrough, the Netgear Powerline 1200 + Extra Outlet (PLP1200-100NAS) is the top performer among adapters with passthrough outlets.
This guide may have been updated by The Wirecutter. To see the current recommendation, please go here.