ESP-NOW MQTT for ESPHome

A battery-friendly ESP-NOW to MQTT bridge for ESPHome, enabling low-power sensors to communicate with Home Assistant without the overhead of Wi-Fi.

What This Does

This library lets you build battery-powered sensors that last months on a single charge by using ESP-NOW instead of Wi-Fi. It consists of two components:

• now_mqtt — Runs on battery-powered sensor nodes. Wakes from deep sleep, reads sensors, broadcasts data via ESP-NOW, goes back to sleep. No Wi-Fi stack, no DHCP, no TCP overhead.

• now_mqtt_bridge — Runs on a mains-powered ESP32 connected to your network. Receives ESP-NOW broadcasts and publishes them to MQTT with Home Assistant auto-discovery.

┌─────────────────┐        ESP-NOW         ┌─────────────────┐        MQTT         ┌─────────────────┐
│  Battery Node   │ ~~~~~~~~~~~~~~~~~~~~>  │     Bridge      │ ───────────────────>│ Home Assistant  │
│  (Deep Sleep)   │      (No Wi-Fi)        │  (Mains Power)  │      (Wi-Fi)        │                 │
└─────────────────┘                        └─────────────────┘                     └─────────────────┘

Attribution & Credits

This is a fork of Microfire's ESPHomeComponents, specifically the now_mqtt and now_mqtt_bridge components.

Original work by: Microfire LLC
Original article: ESP-NOW & MQTT with ESPHome

AI Disclosure

The improvements in this fork were developed with assistance from Claude Code.

Improvements Over Original

Feature	Original	This Fork
Delivery confirmation	Fire-and-forget	Send callback with retry logic (up to 3 attempts)
Wi-Fi channel	Documented as channel 1 only	Configurable via YAML (1-14)
Long-range mode	Always on	Configurable via YAML
Error handling	ESP_ERROR_CHECK (crashes on failure)	Graceful logging, failure callbacks
Device availability	None	Bridge publishes offline status if no packets received within timeout period (default 5 min)
Send result triggers	None	on_send_success / on_send_failure automations

Installation

Add to your ESPHome YAML:

external_components:
  - source:
      type: git
      url: https://github.com/gwlsn/espnowmqtt
    components: [now_mqtt]  # or [now_mqtt_bridge]

Usage

Sensor Node (Battery-Powered)

esphome:
  name: sensor-node

esp32:
  board: firebeetle32

external_components:
  - source:
      type: git
      url: https://github.com/gwlsn/espnowmqtt
    components: [now_mqtt]

# No wifi: block — this node is ESP-NOW only
now_mqtt:
  wifi_channel: 6           # Must match your 2.4GHz AP channel
  long_range_mode: true     # Optional, default true
  on_send_failure:
    - logger.log: "Send failed after retries"

i2c:
  sda: GPIO21
  scl: GPIO22

sensor:
  - platform: bme280_i2c
    temperature:
      name: "Temperature"
    humidity:
      name: "Humidity"

deep_sleep:
  run_duration: 10s
  sleep_duration: 10min

Bridge Node (Mains-Powered)

esphome:
  name: espnow-bridge

esp32:
  board: esp32dev

external_components:
  - source:
      type: git
      url: https://github.com/gwlsn/espnowmqtt
    components: [now_mqtt_bridge]

now_mqtt_bridge:
  wifi_channel: 6            # Wifi channel if `wifi:` component not used (if bridge node is on ethernet)
  publish_availability: true # Publish online/offline status based on user-defined timeout interval

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

mqtt:
  broker: homeassistant.local
  username: !secret mqtt_username
  password: !secret mqtt_password

Configuration Options

now_mqtt (Sensor Node)

Option	Type	Default	Description
wifi_channel	int	1	ESP-NOW channel (1-14). Must match bridge/AP.
long_range_mode	bool	true	Enable Espressif LR protocol for extended range.
on_sent	automation	—	Trigger when data is sent (legacy).
on_send_success	automation	—	Trigger when send confirmed successful.
on_send_failure	automation	—	Trigger when send fails after all retries.

now_mqtt_bridge (Bridge Node)

Option	Type	Default	Description
wifi_channel	int	1	Fallback channel if wifi: component not used.
publish_availability	bool	true	Publish online/offline status (5 min timeout).

Important Notes

Channel Configuration

ESP-NOW requires all devices to be on the same 2.4GHz channel. When your bridge is connected to Wi-Fi, it's locked to whatever channel your access point uses.

1. Check which channel your 2.4GHz AP uses (or set it manually in your router)
2. Use that same channel number in wifi_channel for your sensor nodes
3. It is recommended to lock your 2.4GHz AP to one of channel 1, 6, or 11 (non-overlapping channels) rather than "auto", this prevents the router from switching channels and breaking communication with your sensors

Firmware Updates

The sensor node has no Wi-Fi stack — OTA updates are not possible. You'll need USB access to reflash. This is an intentional tradeoff for battery life.

The bridge node supports OTA normally since it's always connected to Wi-Fi.

Long Range Mode

When long_range_mode: true, the sensor uses Espressif's proprietary LR protocol. This extends range significantly but:

• Both ends must be ESP32 (no ESP8266)
• Throughput is reduced (doesn't matter for sensors)
• Both sender and receiver must have it enabled

License

This project inherits the license from the original Microfire repository. See LICENSE for details.