Key Takeaways
- Check specifically for local energy-data reporting, not just local on/off control — these are sometimes separate features on the same plug
- Zigbee and Z-Wave plugs generally handle local energy reporting reliably
- Confirmed current picks (checked 2026-07-16): Aqara Smart Plug (Zigbee, ~$25-35), Zooz ZEN15 (Z-Wave, $39.95) — Shelly Plus Plug US is discontinued, replaced by Gen4
- See the Energy dashboard setup guide for how these plugs feed into Home Assistant once chosen
Local On/Off vs Local Energy Reporting
A smart plug can be locally controllable (on/off works through Home Assistant without the cloud) while still reporting its detailed energy-usage data only through the manufacturer's cloud API — these are separate capabilities that don't always come together.
- This distinction matters specifically for feeding the Energy dashboard (see that setup guide) — a plug that only controls locally but reports energy via cloud won't give you fully local monitoring for that device.
- Check Home Assistant's own integration documentation for the specific plug model, which typically states explicitly whether energy attributes are available locally or require the cloud integration.
- Sonoff's own lineup is a real, current example of this exact split: the Wi-Fi S31 has built-in energy monitoring, but the Zigbee S31 Lite ZB does not, per Sonoff's own product pages — the same brand, a different capability by model, not just by protocol.
What to Check Before Buying
Confirm local energy-reporting specifically (not just on/off), check the protocol (Zigbee/Z-Wave are generally more reliable for this than Wi-Fi), and verify current Home Assistant integration support for the exact model.
- Search Home Assistant's integration documentation for the exact plug model and confirm energy/power sensor entities are listed as locally available, not cloud-only.
- Zigbee and Z-Wave energy-monitoring plugs generally have a more consistent track record of fully local reporting than Wi-Fi plugs. Aqara's Smart Plug (~$25-35, confirmed on Aqara/Amazon) exposes full energy sensors locally via ZHA or Zigbee2MQTT; Zooz's ZEN15 (Z-Wave 800 series, $39.95, confirmed on getzooz.com) reports wattage, amperage, voltage, and kWh.
- Shelly's plugs document a local HTTP/CoAP/MQTT API across the whole lineup by design (per Shelly's own API documentation), but check availability of the specific current model — the Shelly Plus Plug US is discontinued, replaced by the Shelly Plug US Gen4; its current exact price wasn't confirmable from available sources, so check us.shelly.com directly before buying.
Frequently Asked Questions
Does local on/off control mean energy data is also local?
Not necessarily — some plugs separate these, controlling on/off locally while still routing detailed wattage data through the manufacturer's cloud. Check specifically for local energy-reporting support.
Are Zigbee plugs better than Wi-Fi plugs for energy monitoring?
Generally, yes, for confirmed local reporting — Zigbee and Z-Wave plugs have a more consistent track record here than Wi-Fi plugs, though check the specific model rather than assuming based on protocol alone.
How do these plugs connect to the Energy dashboard?
Once confirmed to report locally, add the plug's energy sensor entity under "Individual Devices" in the Energy dashboard setup — see that guide for the full walkthrough.
Can I mix protocols (some Zigbee, some Wi-Fi plugs)?
Yes — Home Assistant can combine sensor entities from different protocols into the same Energy dashboard view without issue, as long as each individually reports locally.
Do I need one plug per appliance, or can I monitor a whole circuit?
Smart plugs monitor individual appliances plugged into them; for whole-circuit or whole-home monitoring, a CT clamp on the breaker panel (see the local energy management overview) is the appropriate tool instead.
Does every plug in a product line have the same features?
No — Sonoff's Wi-Fi S31 has built-in energy monitoring, but its Zigbee sibling, the S31 Lite ZB, does not, per Sonoff's own product pages. Check the specific model page, not just the brand or family name.
Is the Shelly Plus Plug US still available?
No — it's discontinued and replaced by the Shelly Plug US Gen4. Shelly's whole lineup documents a local HTTP/CoAP/MQTT API by design, but confirm current model availability and price at us.shelly.com before buying.