Symptoms
- Several or all smart devices show offline after the power came back
- Devices that use Wi-Fi are affected more than battery-only devices
- App shows connection errors across many devices at once
- Some devices reconnect on their own after a while, others don't
Likely causes
- CommonModem or router hasn't fully restarted or reconnected to the internetA power outage can leave the router in a state where it needs a manual restart to reconnect properly.
- CommonDevices need time to reconnect one by one after power returnsMany networks briefly get overwhelmed as dozens of devices try to reconnect simultaneously.
- PossibleRouter's DHCP assigned different IP addresses after restart, confusing some devices' cached settingsSome smart devices cache network details that can become stale after a network-wide reset.
- PossibleA specific hub or bridge device didn't restart properlyIf devices route through a hub, a stuck hub will keep everything downstream offline even if Wi-Fi itself is fine.
- Less commonSurge damage to a device from the power eventA significant power surge during the outage recovery can damage device electronics.
What to do
- Restart the modem first, wait for it to fully connect, then restart the router.
- Give the network 5–10 minutes after restarting for all devices to reconnect on their own.
- Restart any smart home hub or bridge device manually as well.
- Power-cycle devices that still show offline after the network is confirmed stable.
- Check for and reconnect any device whose Wi-Fi credentials might need re-entering after a network reset.
- Prioritize checking hub-connected devices, since fixing the hub often restores many devices at once.
- Consider a surge protector or battery backup for your router and hub to reduce future outage-related issues.
Tools and parts
Surge protector or UPS battery backup for router/hubSearch: “UPS battery backup for router”
When to call a pro
If a device was damaged by a power surge and won't power on at all, contact the manufacturer about warranty replacement.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.