diff --git a/nixos/modules/services/home-automation/home-assistant.nix b/nixos/modules/services/home-automation/home-assistant.nix
index 2e91ee55f95e..338c61f89677 100644
--- a/nixos/modules/services/home-automation/home-assistant.nix
+++ b/nixos/modules/services/home-automation/home-assistant.nix
@@ -708,6 +708,9 @@ in {
           "zha"
           "zwave"
           "zwave_js"
+
+          # Custom components, maintained manually.
+          "amshan"
         ];
       in {
         ExecStart = escapeSystemdExecArgs ([
diff --git a/pkgs/development/python-modules/amshan/default.nix b/pkgs/development/python-modules/amshan/default.nix
new file mode 100644
index 000000000000..82eaa056d876
--- /dev/null
+++ b/pkgs/development/python-modules/amshan/default.nix
@@ -0,0 +1,50 @@
+{
+  lib,
+  buildPythonPackage,
+  fetchFromGitHub,
+  setuptools,
+  construct,
+  paho-mqtt,
+  pyserial-asyncio,
+  pytestCheckHook,
+}:
+
+buildPythonPackage rec {
+  pname = "amshan";
+  version = "2.1.1";
+  pyproject = true;
+
+  src = fetchFromGitHub {
+    owner = "toreamun";
+    repo = "amshan";
+    rev = version;
+    hash = "sha256-aw0wTqb2s84STVUN55h6L926pXwaMSppBCfXZVb87w0=";
+  };
+
+  build-system = [
+    setuptools
+  ];
+
+  dependencies = [
+    construct
+    paho-mqtt
+    pyserial-asyncio
+  ];
+
+  nativeCheckInputs = [
+    pytestCheckHook
+  ];
+
+  pythonImportsCheck = [ "han" ];
+
+  meta = {
+    description = "Decode smart power meter data stream of Cosem HDLC frames used by MBUS";
+    longDescription = ''
+      The package has special support of formats for Aidon, Kaifa and Kamstrup
+      meters used in Norway and Sweden (AMS HAN).
+    '';
+    homepage = "https://github.com/toreamun/amshan";
+    license = lib.licenses.mit;
+    maintainers = with lib.maintainers; [ bjornfor ];
+  };
+}
diff --git a/pkgs/servers/home-assistant/custom-components/amshan/package.nix b/pkgs/servers/home-assistant/custom-components/amshan/package.nix
new file mode 100644
index 000000000000..60e55f3edad7
--- /dev/null
+++ b/pkgs/servers/home-assistant/custom-components/amshan/package.nix
@@ -0,0 +1,34 @@
+{
+  lib,
+  fetchFromGitHub,
+  buildHomeAssistantComponent,
+  amshan,
+}:
+
+buildHomeAssistantComponent rec {
+  owner = "toreamun";
+  domain = "amshan";
+  version = "2024.12.0";
+
+  src = fetchFromGitHub {
+    owner = "toreamun";
+    repo = "amshan-homeassistant";
+    tag = version;
+    hash = "sha256-L7TGdUjDvIRP9dHIkng9GYwilmRzhGbUK6ivx8PVtQ4=";
+  };
+
+  dependencies = [
+    amshan
+  ];
+
+  meta = {
+    description = "Home Assistant integration for electricity meters (AMS/HAN/P1)";
+    longDescription = ''
+      The integration supports both streaming (serial port / TCP/IP) and MQTT
+      (Tibber Pulse, energyintelligence.se etc.).
+    '';
+    homepage = "https://github.com/toreamun/amshan-homeassistant";
+    license = lib.licenses.mit;
+    maintainers = with lib.maintainers; [ bjornfor ];
+  };
+}
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 4c25c28cf2c7..3350a6c36841 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -584,6 +584,8 @@ self: super: with self; {
 
   amqtt = callPackage ../development/python-modules/amqtt { };
 
+  amshan = callPackage ../development/python-modules/amshan { };
+
   anchor-kr = callPackage ../development/python-modules/anchor-kr { };
 
   ancp-bids = callPackage ../development/python-modules/ancp-bids { };