diff --git a/homeassistant/components/snmp/switch.py b/homeassistant/components/snmp/switch.py
index e3ce09cbf48..92e27daed6c 100644
--- a/homeassistant/components/snmp/switch.py
+++ b/homeassistant/components/snmp/switch.py
@@ -277,6 +277,11 @@ class SnmpSwitch(SwitchEntity):
                 ):
                     self._state = False
                 else:
+                    _LOGGER.warning(
+                        "Invalid payload '%s' received for entity %s, state is unknown",
+                        resrow[-1],
+                        self.entity_id,
+                    )
                     self._state = None
 
     @property
diff --git a/tests/components/snmp/test_switch.py b/tests/components/snmp/test_switch.py
new file mode 100644
index 00000000000..adb9d1c59d0
--- /dev/null
+++ b/tests/components/snmp/test_switch.py
@@ -0,0 +1,67 @@
+"""SNMP switch tests."""
+
+from unittest.mock import patch
+
+from pysnmp.hlapi import Integer32
+import pytest
+
+from homeassistant.components.switch import DOMAIN as SWITCH_DOMAIN
+from homeassistant.const import STATE_OFF, STATE_ON, STATE_UNKNOWN
+from homeassistant.core import HomeAssistant
+from homeassistant.setup import async_setup_component
+
+config = {
+    SWITCH_DOMAIN: {
+        "platform": "snmp",
+        "host": "192.168.1.32",
+        # ippower-mib::ippoweroutlet1.0
+        "baseoid": "1.3.6.1.4.1.38107.1.3.1.0",
+        "payload_on": 1,
+        "payload_off": 0,
+    },
+}
+
+
+async def test_snmp_integer_switch_off(hass: HomeAssistant) -> None:
+    """Test snmp switch returning int 0 for off."""
+
+    mock_data = Integer32(0)
+    with patch(
+        "homeassistant.components.snmp.switch.getCmd",
+        return_value=(None, None, None, [[mock_data]]),
+    ):
+        assert await async_setup_component(hass, SWITCH_DOMAIN, config)
+        await hass.async_block_till_done()
+        state = hass.states.get("switch.snmp")
+        assert state.state == STATE_OFF
+
+
+async def test_snmp_integer_switch_on(hass: HomeAssistant) -> None:
+    """Test snmp switch returning int 1 for on."""
+
+    mock_data = Integer32(1)
+    with patch(
+        "homeassistant.components.snmp.switch.getCmd",
+        return_value=(None, None, None, [[mock_data]]),
+    ):
+        assert await async_setup_component(hass, SWITCH_DOMAIN, config)
+        await hass.async_block_till_done()
+        state = hass.states.get("switch.snmp")
+        assert state.state == STATE_ON
+
+
+async def test_snmp_integer_switch_unknown(
+    hass: HomeAssistant, caplog: pytest.LogCaptureFixture
+) -> None:
+    """Test snmp switch returning int 3 (not a configured payload) for unknown."""
+
+    mock_data = Integer32(3)
+    with patch(
+        "homeassistant.components.snmp.switch.getCmd",
+        return_value=(None, None, None, [[mock_data]]),
+    ):
+        assert await async_setup_component(hass, SWITCH_DOMAIN, config)
+        await hass.async_block_till_done()
+        state = hass.states.get("switch.snmp")
+        assert state.state == STATE_UNKNOWN
+        assert "Invalid payload '3' received for entity" in caplog.text