2.4 GHz vs 5 GHz vs 6 GHz: which band for which device

Put smart home gear and anything at the far edge of the property on 2.4 GHz, everything that moves around the house on 5 GHz, and stationary high-bandwidth clients in the room with the access point on 6 GHz. What limits 6 GHz indoors is a regulatory power cap, not propagation, and that changes where the band is worth using.

What each band gives you

2.4 GHz carries about 100 MHz and three non-overlapping 20 MHz channels: 1, 6 and 11. 5 GHz carries roughly 500 MHz plus U-NII-4, around 25 channels depending on region, and stops at 160 MHz wide. The US 6 GHz band is 1200 MHz, which yields 59 channels of 20 MHz, 29 of 40 MHz, 14 of 80 MHz and 7 of 160 MHz. Standard power reaches only 850 MHz of that, confined to U-NII-5 (5.925 to 6.425 GHz) and U-NII-7 (6.525 to 6.875 GHz). Per Meraki's Wi-Fi 7 guide, the full band holds three 320 MHz channels; standard power leaves one in the US, two in Canada.

Drawn to one scale. The strip under the 6 GHz bar is why a 1200 MHz headline is not 1200 MHz of usable standard-power spectrum: the two sub-bands that allow it are not even adjacent.

Europe is different. License-exempt Wi-Fi in the EU stops at 6425 MHz, so 480 MHz: one 320 MHz channel, nothing to plan around. In November 2025 the EU's Radio Spectrum Policy Group came down on the mobile side, recommending mobile priority across 6585 to 7125 MHz and holding 6425 to 6585 MHz as a guard band pending WRC-27. The UK took the reverse split in July 2026, giving Wi-Fi priority in that lower 160 MHz. Wi-Fi Alliance calls it the first regulatory framework in Europe covering the entire band, 5925 to 7125 MHz.

Range: the 2 dB almost nobody mentions

Free-space path loss in the first meter runs about 40 dB at 2.4 GHz, 47 dB at 5 GHz and 48 dB at 6 GHz. The step from 5 to 6 GHz costs roughly 2 dB, the step from 2.4 to 5 GHz roughly 7 dB. Extreme Networks, whose figures those are, concludes the effective range difference between 6 GHz and 5 GHz will not be a serious concern in most indoor deployments.

So the claim that 6 GHz barely leaves the room is wrong about the cause. Wall losses do rise with frequency, worst through brick, concrete and stacked floors, but the 5 to 6 GHz gap through a given wall is small next to the 2.4 to 5 GHz gap. What shortens the 6 GHz cell is the power ceiling: a low-power indoor access point is capped at 30 dBm EIRP, its clients at a flat 24 dBm.

The 6 GHz power classes

Class	AP EIRP	AP PSD	Coordination	Where
Standard Power	36 dBm	23 dBm/MHz	AFC required	Indoor and outdoor
Low Power Indoor	30 dBm	5 dBm/MHz	None	Indoor only
Geofenced Variable Power	24 dBm	11 dBm/MHz	Geofencing system	Not fixed outdoor
Very Low Power	14 dBm	-5 dBm/MHz	None	Not fixed outdoor

Geofenced Variable Power is new. The FCC adopted it on 29 January 2026 in the Fourth Report and Order, FCC 26-1. New rule 47 CFR 15.407(a)(7) caps power spectral density at "11 dBm e.i.r.p. in any 1-megahertz band" and EIRP at 24 dBm; clients get 5 dBm/MHz and 18 dBm and must stay 6 dB below the access point. Access points need a permanently attached integrated antenna, and neither GVP nor VLP gear may be mounted on buildings or poles. No consumer GVP hardware has been verified as shipping.

Standard power is boxed into two sub-bands because of incumbent density. As of 5 August 2025 the FCC counted 32,050 fixed-microwave call signs in U-NII-5, 355 in U-NII-6, 16,180 in U-NII-7 and 5,166 in U-NII-8. That is what AFC protects.

Three ways 6 GHz silently fails

WPA3 or OWE are mandatory in 6 GHz. No legacy Open, no WPA2, no mixed mode: whatever the 2.4 and 5 GHz radios accept, the 6 GHz radio advertises WPA3 or Enhanced Open or nothing. One old WPA2 client on that SSID is the commonest cause of "my 6 GHz radio doesn't work."

Passive scanning in 6 GHz targets 15 Preferred Scanning Channels spaced every 80 MHz: 5, 21, 37, 53, 69, 85, 101, 117, 133, 149, 165, 181, 197, 213 and 229. An access point on a non-PSC primary is not invisible, whatever a lot of writing says. Juniper Mist tested Windows, Android, iOS and macOS clients and found all four connect to non-PSC access points through out-of-band discovery, namely "reduced neighbor reports or 802.11k neighbor reports." Prefer a PSC, do not require one.

A 6 GHz-only SSID is a bad idea for the same reason. The Reduced Neighbor Report rides in 2.4 and 5 GHz beacons, so deleting the lower-band beacon deletes the pointer.

DFS gives you channels and charges you stability

Channels 52 to 144 (5250 to 5725 MHz) require dynamic frequency selection under IEEE 802.11h. Channels 36 to 48 and 149 to 165 do not. The tax is a 60-second channel availability check before the access point can serve anyone, 600 seconds on the weather-radar channels 120, 124 and 128. On a match it must vacate within ten seconds and stay off for at least 30 minutes.

False positives, not real radar, are what you will hit: poorly shielded microwave ovens, some frequency-hopping devices, industrial equipment. The response is identical either way. Width compounds it, because an 80 MHz channel spans four 20 MHz sub-channels and a detection on any one evacuates all four. Within 30 to 50 km of an airport, military base or weather radar, keep anything that must not drop off DFS. A mid-session switch is a shrug for a laptop and a dropped call for a VoIP handset.

U-NII-4 adds channels 169, 173 and 177, centered at 5845, 5865 and 5885 MHz, with no DFS duty. The payoff is a third contiguous 160 MHz span, channels 149 through 177, that never watches for radar.

Channel numbers are drawn to scale, so the DFS block really is most of the band. The weather radar channels sit in the middle of it, where a wide channel is most likely to swallow them.

2.4 GHz is load-bearing for the smart home

Zigbee and Thread both run on IEEE 802.15.4 at 2.4 GHz, the same underlying radio, and Matter over Wi-Fi uses your 2.4 GHz network as transport. That trades bandwidth for global spectrum and range per milliwatt, which is what a sensor running years on a coin cell needs. Wi-Fi 6 on 2.4 GHz tops out at 573.5 Mbps PHY for a 2x2 client on 40 MHz, and a PHY rate is a ceiling, not throughput.

Commissioning is where it bites, and the failures are network layer, not radio. Home Assistant's Matter documentation is blunt: "Matter devices often use the 2.4 GHz frequency for Wi-Fi. For this reason, make sure your phone is in the same 2.4 GHz network where you want to operate your devices." It also needs IPv6 multicast moving freely, and warns that VLANs and multicast filtering stop it working.

Microwave ovens radiate near 2.45 GHz and Bluetooth occupies 2.402 to 2.480 GHz; cordless phones, baby monitors, cameras and USB 3.0 ports fill in the rest. Moving a hub off a USB 3.0 dock is a real fix.

Band steering, and why it breaks smart plugs

802.11k supplies neighbor reports so a client knows which access points exist. 802.11v carries the BSS Transition Management frames band steering is built from. Both need client support, 802.11v only suggests, and nothing lets an access point force a client onto a band.

Vendor behavior also changes under you. Cisco Meraki's band steering used to stop advertising the SSID in 2.4 GHz beacons; since MR 29.1 it always advertises the name, and answers a 2.4 GHz probe only if it has not heard that client on 5 GHz in the last 60 seconds. It works "utterly irrespective of the strength of the signal between an AP and a client," and steers one way: "There is no mechanism to steer clients from 5 GHz back to 2.4 GHz."

Sticky clients are the other half: a device holds a degraded association until its driver's threshold trips, then re-authenticates in full.

What to put where

2.4 GHz: Zigbee, Thread and Matter-over-Wi-Fi gear, older plugs and sensors, garden and outbuilding cameras. Expect no throughput.
5 GHz: laptops, tablets, TVs and consoles on DFS channels for the capacity; cameras and VoIP handsets on non-DFS, where a channel switch is unacceptable.
6 GHz: stationary high-bandwidth clients a room away at most, VR headsets, wireless display, anything drowning in neighbors' 5 GHz traffic.
SSID layout: one SSID for 5 and 6 GHz so multi-link operation and Reduced Neighbor Report discovery work, plus a separate 2.4 GHz SSID for 2.4 GHz-only gear. You lose cross-band roaming and gain a router that stops trying to move a smart plug somewhere it cannot go.

Buying notes for 2026

Wi-Fi CERTIFIED 7 requires multi-link operation, preamble puncturing, multiple resource units and WPA3. 6 GHz support, 320 MHz channels and 4096-QAM are optional, and Wi-Fi Alliance's launch announcement qualifies the wide channels as "available in countries that make the 6 GHz band available to Wi-Fi." The TP-Link Archer BE3600 shows what that allows: no 6 GHz radio, 688 and 2882 Mbps sold together as "up to 3.6 Gbps." Read the radio list, not the badge.

MLO is oversold too. STR runs independent radios in parallel; eMLSR uses one radio that listens across bands and transmits on one at a time. Meraki says most client vendors pick one or the other, and that eMLSR trades throughput for lower power draw and cost. On a phone, MLO mostly buys latency. 4096-QAM carries 12 bits per subcarrier instead of 10, but Meraki puts its requirement near 42 dB SNR against 25 dB for 256-QAM. That is a same-room number.

Wi-Fi 8 will not settle the band question either. IEEE 802.11bn applies to carrier frequencies between 1 GHz and 7.250 GHz, so it adds no spectrum and reuses the same three bands. Draft D2.0 has already slipped from May to July 2026, and final approval is scheduled for March 2028. Every Wi-Fi 8 box sold before then is pre-standard silicon.