plug

SONOFF S40 Lite

budget local: good Wi-Fi

Price: budget band last checked Jul 16, 2026
HA fit: good
Offline: yes
Setup: easy
Hub needed: no

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SONOFF S40 Lite

SONOFF

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Quick verdict

The SONOFF S40 Lite is a cheap 15A on/off plug - no energy monitoring (that's the full S40), no Matter, no Thread. Stock eWeLink firmware is cloud-connected by default, but the SonoffLAN integration drives it locally over your network, which is enough for most Home Assistant setups. Know this before you buy: the S40 series runs a Bouffalo Lab BL602 chip rather than an ESP, so despite SONOFF's flashable reputation you cannot put ESPHome or Tasmota on it. If flashing is the point, get the ESP8266-based S31 instead.

Standout: Cheap 15A Wi-Fi plug that answers locally over your LAN on stock firmware.

Notes last checked Jul 16, 2026.

Compatibility snapshot

Home Assistant good

Apple Home none

Google Home okay

Alexa okay

Works offline yes

Setup easy

Extra hub needed no

Power plug-in smart plug

Why it stands out

15A capacity handles most household appliances
local LAN control with stock firmware via the SonoffLAN integration - no flashing needed
very affordable basic on/off Wi-Fi plug

Reasons to hesitate

no energy monitoring - the Lite drops the electricity statistics found on the full S40
stock firmware is cloud-dependent by default via eWeLink
BL602 chip - not an ESP plug, so ESPHome and Tasmota cannot be flashed onto it

Best for

budget on/off control for individual appliances
eWeLink owners who want local LAN control without flashing

Avoid if

you want to run ESPHome or Tasmota on your plugs
you need energy monitoring, Matter, or Thread support

Privacy and local-control notes

Stock eWeLink firmware talks to the SONOFF cloud by default, but the plug also answers on your LAN: the SonoffLAN custom integration (or the official eWeLink add-on) controls it locally over the network. Unlike the older ESP-based SONOFF plugs, the S40 series uses a Bouffalo Lab BL602 chip, so it cannot be reflashed with ESPHome or Tasmota - the community open-firmware option for BL602 is OpenBeken.

Home Assistant support: supported · integration path: SonoffLAN (eWeLink LAN) / eWeLink add-on.

Buying reality check

Price notes: Very budget-friendly. One of the cheapest 15A Wi-Fi plugs available.

Compare side by side: see smart plug comparisons →

Verified against

The compatibility notes above have not been through the source audit yet. The manufacturer's page is here; the notes were last checked Jul 16, 2026.

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Buying guide for this category

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