After researching more than a dozen different options, reviewing National Electrical Code guidelines, talking with safety-testing experts at UL, and cutting apart nine cords to inspect their quality, we recommend the 50-ft Voltec Yellow Outdoor Extension Cord to most people because it has the most durable strain-relief neck, the strongest and smoothest connection, and a rugged outer jacket—all of which should last for years. It's available in 25-foot and 100-foot lengths as well.
Which cord do I need?
You could easily head to the hardware store and grab the cheapest extension cord in the length you need, but not all cords are created equal, nor are they all created for the same tasks. We tend not to think of extension cords as safety devices, but watching an overloaded cord burst into flames really drives that point home. Extension cords are the spark for 3,300 home fires every year in the US, along with 270 injuries and 50 fatalities, according to the Electrical Safety Foundation International and its stats from the US Consumer Product Safety Commission.
The most versatile cords are stamped with a W (in a rating that looks something like 'SJTW') to signify that the jacket is moisture and UV-light resistant. That means it's rated for use in a sunny backyard or a damp basement. Because a well-cared-for extension cord should last years, through any type of household use, all of our top picks that are 25 feet or longer are either W-rated or otherwise moisture and UV resistant.
How we picked
Any cord that's been tested and marked by UL or Intertek (ETL Listed) should perform to its rating when it's brand-new. But that doesn't mean that it's a good value, or that it's built well enough to handle abuse for years on end. So once we were satisfied with the ratings and cost per foot of models—our choices ranged from 50¢ per foot to $1.26 per foot, though some competitors sold for up to $2 per foot—from multiple retailers, we examined the construction of each cord relative to one another to find the details that set the best ones apart.
Our first task was cutting apart each of our brand-new cords and measuring each detail. We also made note of how the receiving end of the extension cord accepted a plug. The receptacles on some cords are too tight and make it hard to properly seat a plug. Any gaps could lead to water infiltration or a possible short (and sparks). Other receptacles can be too loose, allowing a plug to fall or pull out too easily, leading to the same problem.
A good strain-relief neck connection between the plug and the cord prevents the two parts from pulling away and exposing the wiring inside.
If you get only one extension cord, get the Voltec Industries 50-ft Yellow Outdoor Extension Cord. It's not much more expensive than the cords you'll find in a store, but it blows them away in terms of cable quality, connector durability, and most notably, the connection fit. We think 50 feet is a good catchall size, as it's enough to get around a two-car garage, and feed power from one room to another. It's also not as heavy, cumbersome, or expensive as a 100-foot cord. The biggest downside to the Voltec cord is that the huge, durable connector might not fit into tight receptacles—particularly on yard equipment like leaf blowers or hedge trimmers.
Cutting, measuring, and recording data points on a couple handfuls of extension cords made for a pretty dull afternoon until we came across this Voltec cord. We plugged our test cable into it to evaluate the connection, and it was as if triumphant music burst through the clouds. It didn't get (dangerously) stuck halfway in, requiring a jab to seat it completely. It didn't fall out when exposed to a light breeze. It didn't grind into place. The receptacle on this cord is like a velvety vise; after testing so many cheap connections, this one stood out as a product designed and made with care.
Moving from the connector to the cable, the Voltec cord had the longest, most durable strain-relief neck of any we examined.
Runner-up: Less tough for less money, and better with yard equipment
If you want to save a few bucks but still want a quality extension cord, the US Wire 740XX series of cords is almost as good as our top pick from Voltec. The most obvious sacrifice is the less robust strain-relief neck. Though the connector itself is lighted from within and solid, just like on the Voltec, the neck of the cord isn't any longer than the average cord. Because this is an obvious point of failure, we think the Voltec is worth the slightly higher price in most cases. If you'll be using your cord with outdoor equipment that has a pigtail-type plug, the US Wire cord is more likely to work for you. Other than the strain relief, the US Wire cord is just as durable.
An in-store-only pick
Our top pick and runner-up are the best values we could find, but they might not be easy to find in a local brick-and-mortar store. If you need an extension cord now—as in, you're about to drive to a store—the best you can reliably find are the yellow Utilitech Pro cords available at Lowe's. To be clear, this really isn't our favorite cord, as it comes up short on most comparisons with both our top pick and runner-up, and it will generally cost a little more, too. But weirdly, major hardware stores don't stock very good extension cords at competitive prices. The limited strain relief seems like the most obvious point of failure for these cords. Considering they cost more than both our top picks, we'd pick this one up only if we needed to have an extension cord today.
Our pick for light-duty, indoor use
Using an indoor cord correctly is arguably more important than which one you buy, as long as it's made by a reputable company. Indoor cords are meant only for simple, low-power uses like reaching a lamp on your side table or plugging in a phone charger. The GE Wall Hugger Extension Cord does have two advantages to the cheap, nameless cords that you'll find in all corners of the Internet and discount stores. First, the flat plug is safer and less likely to get knocked out when plugged in behind furniture, and second, it's properly tested and rated.
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