Many users notice that their Zigbee network becomes unstable
after enabling WPA3 on a modern WiFi 6 router. Devices disconnect, become
unreachable, or stop responding inside Home Assistant. Although Zigbee and WiFi
operate on different protocols, they often share crowded 2.4GHz airspace—making
any change in WiFi security or modulation potentially disruptive. Here is the
full technical explanation and solution.
⭐ Direct Solution Snippet
Zigbee devices may drop from Home Assistant after enabling
WPA3 because WPA3 can force your router into new 2.4GHz modulation or
compatibility modes, increasing channel interference with Zigbee (especially
channels 11–26). Switching your router to WPA2/WPA3 mixed mode, manually
adjusting your WiFi channel, or relocating the Zigbee coordinator typically
resolves the issue.
Preliminary Diagnostic Steps
Before applying fixes, confirm the root cause using the
following steps:
1. Verify Zigbee Channel Overlap
Check what Zigbee channel your coordinator is using:
In Home Assistant →
Settings → Integrations → Zigbee → Configuration
If it is 11, 12, or
13, interference with your router's 2.4GHz channel (1, 6, or 11) is highly
likely.
2. Check Your WiFi 6 Router Mode
WPA3 may automatically enable:
802.11ax 2.4GHz OFDMA
High power
transmission
Mandatory Protected
Management Frames (PMF)
These increase noise for Zigbee.
3. Monitor Zigbee Mesh Health
View:
LQI (Link Quality
Indicator)
RSSI levels
Last seen timestamps
If many nodes go offline simultaneously after enabling WPA3,
it’s almost certainly a radio interference issue.
4. Inspect Placement of the Zigbee Coordinator
Check if your USB coordinator is:
Too close to the WiFi
router
Plugged directly into
the Home Assistant host
Surrounded by metal
or other radio equipment
StepbyStep Technical Fix
1️⃣ Switch Router to WPA2/WPA3 Mixed Mode
Login to your router → Wireless Security
Change from WPA3Only
to WPA2/WPA3 Mixed Mode
This reduces radio stress and restores compatibility.
2️⃣ Manually Set a Safer WiFi Channel
Use:
Channel 1 → Avoids
Zigbee channels 15–26
Channel 6 → Avoids
Zigbee channels 20–26
Channel 11 → Avoids
Zigbee channels 11–17
Recommended for Zigbee stability:
Zigbee Channel 20 or
25
WiFi Channel 1
3️⃣ Move the Zigbee Coordinator Away From the Router
Use:
A 1–2 meter USB
extension cable
Reduce router
transmit power to 75%
This prevents signal saturation.
4️⃣ Disable 2.4GHz AX Mode Temporarily (Optional)
Some routers allow disabling 802.11ax specifically on
2.4GHz.
This is known to greatly reduce Zigbee interference.
5️⃣ Reboot the Zigbee Mesh
After making changes:
Reboot Home Assistant
Powercycle Zigbee
devices
Allow 30–60 minutes
for mesh rebalancing
6️⃣ Update Firmware
Update:
Router firmware
Zigbee coordinator
firmware (e.g., Sonoff ZBDongleP/E, ConBee II)
Zigbee integration in
Home Assistant
Preventing Future Conflict
✔
Use a HighQuality Zigbee Coordinator
Recommended:
Sonoff ZBDongleP
(Texas Instruments)
Home Assistant
SkyConnect
They handle interference better.
✔
Assign a Static IP to your Home Assistant host
This stabilizes integrations and prevents reconnection
delays.
✔
Keep WiFi and Zigbee on NonOverlapping Channels
Best longterm configuration:
WiFi → Channel 1
Zigbee → Channel 20
or 25
✔
Add Zigbee Routers (Repeaters)
Devices like:
IKEA Tradfri
repeaters
Sonoff Zigbee USB
repeaters
These strengthen the mesh and prevent singlepoint failures.
✔
Avoid Router Placement Mistakes
Do NOT place the router next to:
Zigbee sticks
Smart hubs
USB 3.0 cables
Metal shelves