There is one setting on your router that’s ultra-tempting to crank all the way to 11. You’ve seen it there, winking at you: it’s the channel width slider.

In theory, pushing your Wi-Fi band channel width from 20MHz to 160MHz will solve some of your connectivity issues. In reality, it’ll probably make most of them worse, and give you some new ones to think about.

That’s not to say that there isn’t a right time to push up the channel width; it’s just knowing when it’s actually worth doing.

Increasing channel width on 2.4GHz is pointless

It overlaps enough already

The 2.4GHz band is probably the most common band in use worldwide, and that means its channels are typically crowded.

Within the 2.4GHz band, there are only three 20MHz channels that don’t overlap: 1, 6, and 11. If you bond two of them into a 40MHz channel, you’re basically gluing together other channels that do overlap, and likely going to start experiencing interference from your neighbors’ Wi-Fi.

2.4GHz channel bonding is something most routers have already done away with; at least, they don’t make the setting easy to find for this reason. Way back when, in the days of Wi-Fi 4 (802.11n), 40MBHz bonded channels were marketed as a speed boost.

In fairness, Wi-Fi channels weren’t quite as busy back then, but it still wasn’t a great idea. Similarly, if you live in the middle of nowhere with no overlapping Wi-Fi signals, bonding your 2.4GHz Wi-Fi channels isn’t going to cause any harm, as there is no interference to contend with. But for most folks, it’s a bad idea.

It’s more feasible on 5GHz Wi-Fi

But still not without issues, especially in radar-restricted spectrum

The 5GHz band has more available spectrum than 2.4GHz, which makes it a better prospect for channel bonding. But before you head to your router and start adjusting channel widths, there are some other considerations.

A portion of the 5GHz band — the UNII-2A and UNII-2C ranges — is shared with radar systems used for weather tracking, aviation, and military use.

Routers operating on these channels are legally required to run Dynamic Frequency Selection (DFS), which listens for radar activity and vacates the channel the moment it detects any. Most of the time, if you push your channel width to 80 or 160MHz, you’ll almost always end up spanning at least one DFS channel, simply because there aren’t enough non-DFS channels left in the band to build a wide one without doing so.

But there are exceptions. For example, the 80MHz channel 42 (spanning 20MHz channels 36-48) doesn’t cross a DFS channel. Similar for 80MHz channel 155 (spanning 20MHz channels 149-161).

As you might expect, intrusion into restricted broadcasting spectrums isn’t without consequence. I don’t mean guys in black suits knocking at your door within minutes. But your router has to run what’s known as a Channel Availability Check before it starts transmitting on a DFS channel, silently listening for radar for around a minute, and sometimes considerably longer, depending on the channel, before your network even comes up.

Then, if any radar is detected nearby, your router will just abandon the channel, and your channel bonding in the process. When that happens, every connected device briefly disconnects while the router moves to another channel.

That’s for really broad channels, mind. If you stick to smaller increases to your channel width, say, boosting from 20MHz to 40MHz, you’ll avoid the DFS blocks entirely and increase your channel throughput. Non-DFS spectrum exists in two blocks (channels 36 to 48 (UNII-1) and channels 149 to 165 (UNII-3) in most regions) and a 40MHz channel fits inside either one.

The 6GHz Wi-Fi band is where wide channels really works

It’s built for the job

The rollout of Wi-Fi 6E didn’t just bring speed boosts. It also unlocked an entirely new broadcasting spectrum: 6GHz. That meant for the first time in many years, there was an entirely new set of airwaves to broadcast Wi-Fi on, which means a whole lot of airspace without heaps of competing signals — basically the opposite of 2.4GHz!

Available on Wi-Fi 6E and now Wi-Fi 7, 6GHz is perfect for wide Wi-Fi channels for a number of reasons. The Wi-Fi band spans up to 1,200MHz of spectrum, which is more than double everything available across the entire 5GHz band combined (in the US — other countries are more restrictive), and almost none of it carries the legacy baggage that 2.4GHz and 5GHz have picked up over two decades of devices piling onto the same channels.

6GHz was also built from the ground up with wide Wi-Fi channels in mind. Unlike 2.4GHz and 5GHz, 6GHz channels are spaced appropriately to combine nicely into broader channels. There’s room for multiple 160MHz channels, or several 320MHz ones on Wi-Fi 7, without any of them touching each other.

There are 59 individual 20MHz channels, numbered 1, 5, 9, and so on up to 233, which group into fixed, non-overlapping wide channels instead of being bonded together on the fly. Combined, that gives 29 separate 40MHz channels, 14 separate 80MHz channels, seven separate 160MHz channels, and, once you’re on Wi-Fi 7’s 320MHz mode, four separate 320MHz channels. In that, there is no having to search for a collection of clean channels like on 5GHz, as the network was specifically designed for this.

It’s not entirely free of restrictions, mind. Higher-power 6GHz operation is gated by something called Automated Frequency Coordination (AFC), which checks a router’s location against a database of incumbent users (fixed microwave links, mostly) before allowing full-power transmission.

In practice, it’s similar to DFS, but instead of listening for interference, it checks against a database. But most home routers running the 6GHz band run under what’s known as Low-Power Indoor rules, which helps it skip some of the restrictions associated with DFS.

Widening is really down to your Wi-Fi generation

So, the answer isn’t “don’t widen your Wi-Fi channels.” It’s more “only widen them if your Wi-Fi band can actually support them.” Wider channels absolutely can make Wi-Fi faster, but only when there’s enough clean spectrum to go around.

On congested 2.4GHz networks, they’re usually a downgrade. On 5GHz, they’re much more situational, with wider channels becoming harder to fit into the available spectrum and often forcing your router onto DFS channels. It’s really only on 6GHz, where the band was designed around wide channels from day one, that cranking things up to 160MHz or even 320MHz consistently delivers the kind of speed boost the marketing promises.

Wider channels also have another issue: range. Creating wide Wi-Fi channels requires your devices to maintain a stronger signal across a larger spectrum range. As you move farther away from your router, or start putting walls between you and it, a 20MHz or 40MHz connection will often remain stable where an 80MHz or 160MHz connection begins to slow down or drop to a narrower channel.

If you do decide to experiment with your router’s channel width, treat it as exactly that: an experiment. Run a few speed tests in the rooms where you actually use Wi-Fi, see how your devices behave over a few days, and don’t be afraid to switch back if performance becomes less consistent!