diff --git a/lib/localiser/domain/schema/sensor.ex b/lib/localiser/domain/schema/sensor.ex
index 2c67468..d0ef267 100644
--- a/lib/localiser/domain/schema/sensor.ex
+++ b/lib/localiser/domain/schema/sensor.ex
@@ -8,6 +8,7 @@ defmodule Localiser.Domain.Schema.Sensor do
   schema "sensors" do
     field :sensor_id, :string
     field :confirmed, :boolean, default: false
+    field :firmware_version, :string
     field :x, :float
     field :y, :float
     field :floor_x, :float, virtual: true
@@ -22,7 +23,7 @@ defmodule Localiser.Domain.Schema.Sensor do
   @doc false
   def changeset(sensor, attrs) do
     sensor
-    |> cast(attrs, [:sensor_id, :confirmed, :room_id, :x, :y])
+    |> cast(attrs, [:sensor_id, :confirmed, :firmware_version, :room_id, :x, :y])
     |> validate_required([:sensor_id])
     |> unique_constraint(:sensor_id)
     |> assoc_constraint(:room)
diff --git a/lib/localiser/domain/sensors.ex b/lib/localiser/domain/sensors.ex
index de1d831..b0d5c7c 100644
--- a/lib/localiser/domain/sensors.ex
+++ b/lib/localiser/domain/sensors.ex
@@ -59,9 +59,29 @@ defmodule Localiser.Domain.Sensors do
     {:ok, sensor}
   end
 
+  @version_timeout_ms 5_000
+
   def get_version(%Sensor{} = sensor) do
-    Localiser.MQTT.Connection.publish(cmd_topic(sensor), Jason.encode!(%{action: "version"}))
-    {:ok, sensor}
+    :ok = Phoenix.PubSub.subscribe(Localiser.PubSub, "sensors")
+
+    case Localiser.MQTT.Connection.publish(cmd_topic(sensor), Jason.encode!(%{action: "version"})) do
+      :ok ->
+        result =
+          receive do
+            {:sensor_announced, %Sensor{sensor_id: sid, firmware_version: v}}
+            when sid == sensor.sensor_id and not is_nil(v) ->
+              {:ok, v}
+          after
+            @version_timeout_ms -> {:error, :timeout}
+          end
+
+        Phoenix.PubSub.unsubscribe(Localiser.PubSub, "sensors")
+        result
+
+      error ->
+        Phoenix.PubSub.unsubscribe(Localiser.PubSub, "sensors")
+        error
+    end
   end
 
   def send_ota_update(%Sensor{} = sensor, url, version) do
@@ -169,12 +189,22 @@ defmodule Localiser.Domain.Sensors do
 
   # Called when an ESP board self-announces on MQTT. Inserts a new unplaced sensor
   # record, or marks it confirmed if the sensor_id already exists.
-  def upsert_announced(sensor_id) do
+  def upsert_announced(sensor_id, firmware_version \\ nil) do
+    attrs = %{sensor_id: sensor_id, confirmed: true}
+    attrs = if firmware_version, do: Map.put(attrs, :firmware_version, firmware_version), else: attrs
+
+    on_conflict =
+      if firmware_version do
+        [set: [confirmed: true, firmware_version: firmware_version, updated_at: DateTime.utc_now()]]
+      else
+        [set: [confirmed: true, updated_at: DateTime.utc_now()]]
+      end
+
     result =
       %Sensor{}
-      |> Sensor.changeset(%{sensor_id: sensor_id, confirmed: true})
+      |> Sensor.changeset(attrs)
       |> Repo.insert(
-        on_conflict: [set: [confirmed: true, updated_at: DateTime.utc_now()]],
+        on_conflict: on_conflict,
         conflict_target: :sensor_id,
         returning: true
       )
diff --git a/lib/localiser/mqtt/router.ex b/lib/localiser/mqtt/router.ex
index 5d1fd0d..0112e59 100644
--- a/lib/localiser/mqtt/router.ex
+++ b/lib/localiser/mqtt/router.ex
@@ -30,7 +30,7 @@ defmodule Localiser.MQTT.Router do
         handle_rssi(sensor_id, payload)
 
       {:announce, sensor_id} ->
-        handle_announce(sensor_id)
+        handle_announce(sensor_id, payload)
 
       {:error, :invalid_topic} ->
         Logger.debug("[MQTT.Router] Received message with invalid topic: #{topic}")
@@ -70,8 +70,14 @@ defmodule Localiser.MQTT.Router do
     end
   end
 
-  defp handle_announce(sensor_id) do
-    case Sensors.upsert_announced(sensor_id) do
+  defp handle_announce(sensor_id, payload) do
+    version =
+      case Jason.decode(payload) do
+        {:ok, %{"version" => v}} when is_binary(v) -> v
+        _ -> nil
+      end
+
+    case Sensors.upsert_announced(sensor_id, version) do
       {:ok, _sensor} ->
         Logger.info("[MQTT.Router] Sensor announced: #{sensor_id}")
 
diff --git a/lib/localiser/web/controllers/sensor_controller.ex b/lib/localiser/web/controllers/sensor_controller.ex
index cb3a24d..be1e652 100644
--- a/lib/localiser/web/controllers/sensor_controller.ex
+++ b/lib/localiser/web/controllers/sensor_controller.ex
@@ -241,8 +241,8 @@ defmodule Localiser.Web.Controllers.SensorController do
 
   def get_version(conn, %{"id" => id}) do
     sensor = Sensors.get_sensor!(id)
-    {:ok, _} = Sensors.get_version(sensor)
-    json(conn, %{status: "ok"})
+    {:ok, version} = Sensors.get_version(sensor)
+    json(conn, %{status: "ok", version: version})
   end
 
   def reconfigure(conn, %{"id" => id} = params) do
diff --git a/priv/repo/migrations/20260520192900_add_firmware_version_to_sensors.exs b/priv/repo/migrations/20260520192900_add_firmware_version_to_sensors.exs
new file mode 100644
index 0000000..8f771dc
--- /dev/null
+++ b/priv/repo/migrations/20260520192900_add_firmware_version_to_sensors.exs
@@ -0,0 +1,9 @@
+defmodule Localiser.Repo.Migrations.AddFirmwareVersionToSensors do
+  use Ecto.Migration
+
+  def change do
+    alter table(:sensors) do
+      add :firmware_version, :string
+    end
+  end
+end