diff --git a/kasa/cli.py b/kasa/cli.py
index 48ce039c..b2d9d91a 100755
--- a/kasa/cli.py
+++ b/kasa/cli.py
@@ -99,6 +99,12 @@ def json_formatter_cb(result, **kwargs):
     required=False,
     help="The host name or IP address of the device to connect to.",
 )
+@click.option(
+    "--port",
+    envvar="KASA_PORT",
+    required=False,
+    help="The port of the device to connect to.",
+)
 @click.option(
     "--alias",
     envvar="KASA_NAME",
@@ -125,7 +131,7 @@ def json_formatter_cb(result, **kwargs):
 )
 @click.version_option(package_name="python-kasa")
 @click.pass_context
-async def cli(ctx, host, alias, target, debug, type, json):
+async def cli(ctx, host, port, alias, target, debug, type, json):
     """A tool for controlling TP-Link smart home devices."""  # noqa
     # no need to perform any checks if we are just displaying the help
     if sys.argv[-1] == "--help":
@@ -179,7 +185,7 @@ async def cli(ctx, host, alias, target, debug, type, json):
         dev = TYPE_TO_CLASS[type](host)
     else:
         echo("No --type defined, discovering..")
-        dev = await Discover.discover_single(host)
+        dev = await Discover.discover_single(host, port=port)
 
     await dev.update()
     ctx.obj = dev
@@ -275,6 +281,7 @@ async def state(dev: SmartDevice):
     """Print out device state and versions."""
     echo(f"[bold]== {dev.alias} - {dev.model} ==[/bold]")
     echo(f"\tHost: {dev.host}")
+    echo(f"\tPort: {dev.port}")
     echo(f"\tDevice state: {dev.is_on}")
     if dev.is_strip:
         echo("\t[bold]== Plugs ==[/bold]")
diff --git a/kasa/discover.py b/kasa/discover.py
index 217ec32c..f7b5fbbf 100755
--- a/kasa/discover.py
+++ b/kasa/discover.py
@@ -193,19 +193,19 @@ class Discover:
         return protocol.discovered_devices
 
     @staticmethod
-    async def discover_single(host: str) -> SmartDevice:
+    async def discover_single(host: str, *, port: Optional[int] = None) -> SmartDevice:
         """Discover a single device by the given IP address.
 
         :param host: Hostname of device to query
         :rtype: SmartDevice
         :return: Object for querying/controlling found device.
         """
-        protocol = TPLinkSmartHomeProtocol(host)
+        protocol = TPLinkSmartHomeProtocol(host, port=port)
 
         info = await protocol.query(Discover.DISCOVERY_QUERY)
 
         device_class = Discover._get_device_class(info)
-        dev = device_class(host)
+        dev = device_class(host, port=port)
         await dev.update()
 
         return dev
diff --git a/kasa/protocol.py b/kasa/protocol.py
index e21866e3..cd9066c6 100755
--- a/kasa/protocol.py
+++ b/kasa/protocol.py
@@ -33,9 +33,10 @@ class TPLinkSmartHomeProtocol:
     DEFAULT_TIMEOUT = 5
     BLOCK_SIZE = 4
 
-    def __init__(self, host: str) -> None:
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
         """Create a protocol object."""
         self.host = host
+        self.port = port or TPLinkSmartHomeProtocol.DEFAULT_PORT
         self.reader: Optional[asyncio.StreamReader] = None
         self.writer: Optional[asyncio.StreamWriter] = None
         self.query_lock: Optional[asyncio.Lock] = None
@@ -78,7 +79,7 @@ class TPLinkSmartHomeProtocol:
         if self.writer:
             return
         self.reader = self.writer = None
-        task = asyncio.open_connection(self.host, TPLinkSmartHomeProtocol.DEFAULT_PORT)
+        task = asyncio.open_connection(self.host, self.port)
         self.reader, self.writer = await asyncio.wait_for(task, timeout=timeout)
 
     async def _execute_query(self, request: str) -> Dict:
@@ -133,13 +134,13 @@ class TPLinkSmartHomeProtocol:
             except ConnectionRefusedError as ex:
                 await self.close()
                 raise SmartDeviceException(
-                    f"Unable to connect to the device: {self.host}: {ex}"
+                    f"Unable to connect to the device: {self.host}:{self.port}: {ex}"
                 )
             except OSError as ex:
                 await self.close()
                 if ex.errno in _NO_RETRY_ERRORS or retry >= retry_count:
                     raise SmartDeviceException(
-                        f"Unable to connect to the device: {self.host}: {ex}"
+                        f"Unable to connect to the device: {self.host}:{self.port}: {ex}"
                     )
                 continue
             except Exception as ex:
@@ -147,7 +148,7 @@ class TPLinkSmartHomeProtocol:
                 if retry >= retry_count:
                     _LOGGER.debug("Giving up on %s after %s retries", self.host, retry)
                     raise SmartDeviceException(
-                        f"Unable to connect to the device: {self.host}: {ex}"
+                        f"Unable to connect to the device: {self.host}:{self.port}: {ex}"
                     )
                 continue
 
@@ -162,7 +163,7 @@ class TPLinkSmartHomeProtocol:
                 if retry >= retry_count:
                     _LOGGER.debug("Giving up on %s after %s retries", self.host, retry)
                     raise SmartDeviceException(
-                        f"Unable to query the device {self.host}: {ex}"
+                        f"Unable to query the device {self.host}:{self.port}: {ex}"
                     ) from ex
 
                 _LOGGER.debug(
diff --git a/kasa/smartbulb.py b/kasa/smartbulb.py
index b28edab1..1d6ba31e 100644
--- a/kasa/smartbulb.py
+++ b/kasa/smartbulb.py
@@ -199,8 +199,8 @@ class SmartBulb(SmartDevice):
     SET_LIGHT_METHOD = "transition_light_state"
     emeter_type = "smartlife.iot.common.emeter"
 
-    def __init__(self, host: str) -> None:
-        super().__init__(host=host)
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
+        super().__init__(host=host, port=port)
         self._device_type = DeviceType.Bulb
         self.add_module("schedule", Schedule(self, "smartlife.iot.common.schedule"))
         self.add_module("usage", Usage(self, "smartlife.iot.common.schedule"))
diff --git a/kasa/smartdevice.py b/kasa/smartdevice.py
index 75efcded..fd8d3768 100755
--- a/kasa/smartdevice.py
+++ b/kasa/smartdevice.py
@@ -191,14 +191,15 @@ class SmartDevice:
 
     emeter_type = "emeter"
 
-    def __init__(self, host: str) -> None:
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
         """Create a new SmartDevice instance.
 
         :param str host: host name or ip address on which the device listens
         """
         self.host = host
+        self.port = port
 
-        self.protocol = TPLinkSmartHomeProtocol(host)
+        self.protocol = TPLinkSmartHomeProtocol(host, port=port)
         _LOGGER.debug("Initializing %s of type %s", self.host, type(self))
         self._device_type = DeviceType.Unknown
         # TODO: typing Any is just as using Optional[Dict] would require separate checks in
diff --git a/kasa/smartdimmer.py b/kasa/smartdimmer.py
index 9565437d..247455e3 100644
--- a/kasa/smartdimmer.py
+++ b/kasa/smartdimmer.py
@@ -62,8 +62,8 @@ class SmartDimmer(SmartPlug):
 
     DIMMER_SERVICE = "smartlife.iot.dimmer"
 
-    def __init__(self, host: str) -> None:
-        super().__init__(host)
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
+        super().__init__(host, port=port)
         self._device_type = DeviceType.Dimmer
         # TODO: need to be verified if it's okay to call these on HS220 w/o these
         # TODO: need to be figured out what's the best approach to detect support for these
diff --git a/kasa/smartlightstrip.py b/kasa/smartlightstrip.py
index 566bf0a7..6afe5d11 100644
--- a/kasa/smartlightstrip.py
+++ b/kasa/smartlightstrip.py
@@ -41,8 +41,8 @@ class SmartLightStrip(SmartBulb):
     LIGHT_SERVICE = "smartlife.iot.lightStrip"
     SET_LIGHT_METHOD = "set_light_state"
 
-    def __init__(self, host: str) -> None:
-        super().__init__(host)
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
+        super().__init__(host, port=port)
         self._device_type = DeviceType.LightStrip
 
     @property  # type: ignore
diff --git a/kasa/smartplug.py b/kasa/smartplug.py
index d49e4054..94a5e350 100644
--- a/kasa/smartplug.py
+++ b/kasa/smartplug.py
@@ -1,6 +1,6 @@
 """Module for smart plugs (HS100, HS110, ..)."""
 import logging
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 from kasa.modules import Antitheft, Cloud, Schedule, Time, Usage
 from kasa.smartdevice import DeviceType, SmartDevice, requires_update
@@ -37,8 +37,8 @@ class SmartPlug(SmartDevice):
     For more examples, see the :class:`SmartDevice` class.
     """
 
-    def __init__(self, host: str) -> None:
-        super().__init__(host)
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
+        super().__init__(host, port=port)
         self._device_type = DeviceType.Plug
         self.add_module("schedule", Schedule(self, "schedule"))
         self.add_module("usage", Usage(self, "schedule"))
diff --git a/kasa/smartstrip.py b/kasa/smartstrip.py
index 69ea03e5..a970925b 100755
--- a/kasa/smartstrip.py
+++ b/kasa/smartstrip.py
@@ -79,8 +79,8 @@ class SmartStrip(SmartDevice):
     For more examples, see the :class:`SmartDevice` class.
     """
 
-    def __init__(self, host: str) -> None:
-        super().__init__(host=host)
+    def __init__(self, host: str, *, port: Optional[int] = None) -> None:
+        super().__init__(host=host, port=port)
         self.emeter_type = "emeter"
         self._device_type = DeviceType.Strip
         self.add_module("antitheft", Antitheft(self, "anti_theft"))
diff --git a/kasa/tests/test_discovery.py b/kasa/tests/test_discovery.py
index 52325f39..bbdaf8a8 100644
--- a/kasa/tests/test_discovery.py
+++ b/kasa/tests/test_discovery.py
@@ -52,12 +52,14 @@ async def test_type_unknown():
         Discover._get_device_class(invalid_info)
 
 
-async def test_discover_single(discovery_data: dict, mocker):
+@pytest.mark.parametrize("custom_port", [123, None])
+async def test_discover_single(discovery_data: dict, mocker, custom_port):
     """Make sure that discover_single returns an initialized SmartDevice instance."""
     mocker.patch("kasa.TPLinkSmartHomeProtocol.query", return_value=discovery_data)
-    x = await Discover.discover_single("127.0.0.1")
+    x = await Discover.discover_single("127.0.0.1", port=custom_port)
     assert issubclass(x.__class__, SmartDevice)
     assert x._sys_info is not None
+    assert x.port == custom_port
 
 
 INVALIDS = [
diff --git a/kasa/tests/test_protocol.py b/kasa/tests/test_protocol.py
index 7aa95a5a..b438f498 100644
--- a/kasa/tests/test_protocol.py
+++ b/kasa/tests/test_protocol.py
@@ -129,6 +129,36 @@ async def test_protocol_logging(mocker, caplog, log_level):
         assert "success" not in caplog.text
 
 
+@pytest.mark.parametrize("custom_port", [123, None])
+async def test_protocol_custom_port(mocker, custom_port):
+    encrypted = TPLinkSmartHomeProtocol.encrypt('{"great":"success"}')[
+        TPLinkSmartHomeProtocol.BLOCK_SIZE :
+    ]
+
+    async def _mock_read(byte_count):
+        nonlocal encrypted
+        if byte_count == TPLinkSmartHomeProtocol.BLOCK_SIZE:
+            return struct.pack(">I", len(encrypted))
+        if byte_count == len(encrypted):
+            return encrypted
+        raise ValueError(f"No mock for {byte_count}")
+
+    def aio_mock_writer(_, port):
+        reader = mocker.patch("asyncio.StreamReader")
+        writer = mocker.patch("asyncio.StreamWriter")
+        if custom_port is None:
+            assert port == 9999
+        else:
+            assert port == custom_port
+        mocker.patch.object(reader, "readexactly", _mock_read)
+        return reader, writer
+
+    protocol = TPLinkSmartHomeProtocol("127.0.0.1", port=custom_port)
+    mocker.patch("asyncio.open_connection", side_effect=aio_mock_writer)
+    response = await protocol.query({})
+    assert response == {"great": "success"}
+
+
 def test_encrypt():
     d = json.dumps({"foo": 1, "bar": 2})
     encrypted = TPLinkSmartHomeProtocol.encrypt(d)