ESP32 wM-Bus Gateway Links Meters to Home Assistant
IoTLabs' open-source ESP32 wM-Bus Gateway reads 868 MHz utility meters and feeds the data to Home Assistant via ESPHome — no cloud, about $50.
An ESP32 Gateway That Brings Utility Meters Into Home Assistant
Smart-home tinkerers who want real visibility into their water, gas, and heat usage just got a tidy, local-first tool. On July 14, 2026, Poland's IoTLabs released the wM-Bus Gateway, an assembled, open-source ESP32 device that listens to Wireless M-Bus utility meters and pipes their readings straight into Home Assistant via ESPHome. Best of all, it keeps everything on your own network — no cloud account, no subscription, just your data on your terms.
- What it is: A pre-assembled ESP32 gateway that receives Wireless M-Bus (wM-Bus) meter data and integrates with Home Assistant through ESPHome
- The radio: An 868 MHz Semtech SX1276 (RFM95/96) that decodes both T1 and C1 wM-Bus frames using the open wmbusmeters library
- Nice touches: A 1.3-inch OLED status display, an external SMA antenna, and a bonus role as a Bluetooth proxy for nearby BLE sensors
- Openness and price: Source and binaries on GitHub, roughly $50 on Tindie and Lectronz, in a compact 70 x 36 x 15 mm case
What Is Wireless M-Bus, and Why Read It Locally?
Wireless M-Bus is the radio standard many European utility meters use to broadcast consumption data at 868 MHz. The catch has always been that this data often flows to the utility, not to you — even though it is your usage. The IoTLabs gateway flips that around: its SX1276 radio picks up the T1 and C1 frames your meters already transmit, decodes them with the open-source wmbusmeters library, and publishes the readings locally over MQTT, a native API, REST, or TCP/UDP. Drop it into Home Assistant and you get live water, gas, or heat figures on your own dashboards, entirely under your control.
A Handy Two-in-One for the Smart Home
Because it is built on a dual-core ESP32 with both Wi-Fi and Bluetooth, the gateway does double duty as a Bluetooth proxy, extending the range of your BLE temperature and humidity sensors while it monitors your meters. The 1.3-inch OLED gives you an at-a-glance status readout, and the external SMA antenna helps it hear meters tucked away in basements or utility closets. It is the same self-hosted, no-cloud philosophy that runs through so many great ESP32 and single-board projects — capability you own outright.
Local-First, Open, and Ready to Go
What makes the wM-Bus Gateway so appealing is that it ships assembled and open at the same time: about $50 gets you a finished device, and the full source lives on GitHub if you want to tweak or extend it. For anyone building a privacy-respecting smart home, turning previously locked-away meter data into friendly Home Assistant sensors — with no cloud in the loop — is a genuinely useful and empowering upgrade.
Sources: CNX Software — July 14, 2026; IoTLabs Product Page — July 2026.
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