diff --git a/homeassistant/helpers/config_validation.py b/homeassistant/helpers/config_validation.py
index 9ce4b6b166dd4a..b412a5d44bb0c3 100644
--- a/homeassistant/helpers/config_validation.py
+++ b/homeassistant/helpers/config_validation.py
@@ -474,6 +474,60 @@ def validator(config):
     return validator
 
 
+def is_mac_address(value=None, separators=None, allow_lowercase=True,
+                   allow_uppercase=True, chunk=2):
+    """Validate that a value is a MAC address."""
+    if not allow_lowercase and not allow_uppercase:
+        raise vol.Invalid("Must not disallow upper and lowercase")
+
+    if separators is None:
+        separators = ['', '.', ':', '-']
+    elif not isinstance(separators, list):
+        raise vol.Invalid('separators must be a list')
+
+    if 12 % chunk != 0:
+        raise vol.Invalid("Invalid chunk size for MAC address")
+
+    characters = ["0-9"]
+    if allow_lowercase:
+        characters.append("a-z")
+    if allow_uppercase:
+        characters.append("A-Z")
+
+    repeat = int(12 / chunk)
+    character_class = "[%s]{%s}" % ("".join(characters), chunk)
+    format_list = []
+
+    for s in separators:
+        if s == '':
+            format_list.append(s.join([character_class] * repeat))
+        else:
+            sep = "[%s]{1}" % re.escape(s)
+            format_list.append(sep.join([character_class] * repeat))
+
+    regex_list = []
+    for f in format_list:
+        regex_list.append(re.compile("^%s$" % f))
+
+    def validator(value: Any) -> str:
+        """Validate that the value is a MAC address."""
+        if not isinstance(value, str):
+            raise vol.Invalid('not a string value: {}'.format(value))
+
+        matches = False
+        for r in regex_list:
+            if r.match(value):
+                matches = True
+                break
+
+        if not matches:
+            err = "value {} is not a permitted MAC address".format(value)
+            raise vol.Invalid(err)
+
+        return value
+    return validator
+
+
 # Validator helpers
 
 def key_dependency(key, dependency):
diff --git a/tests/helpers/test_config_validation.py b/tests/helpers/test_config_validation.py
index cfd84dbc3b3b0a..a68f5ecca4340f 100644
--- a/tests/helpers/test_config_validation.py
+++ b/tests/helpers/test_config_validation.py
@@ -584,3 +584,74 @@ def test_is_regex():
 
     valid_re = ".*"
     schema(valid_re)
+
+
+def test_is_mac_address():
+    """Test the mac_address validator."""
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(separators=True))
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(chunk=11))
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(allow_lowercase=False,
+                                              allow_uppercase=False))
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(allow_uppercase=False))
+        schema('0123456789AB')
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(allow_lowercase=False))
+        schema('0123456789ab')
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(separators=[':']))
+        schema('01-23-45-67-89-ab')
+
+    with pytest.raises(vol.Invalid):
+        schema = vol.Schema(cv.is_mac_address(separators=[':']))
+        schema('not a mac!')
+
+    test_2_chunk = [
+        '01:23:45:67:89:AB',
+        '01:23:45:67:89:ab',
+        '01.23.45.67.89.AB',
+        '01.23.45.67.89.ab',
+        '01-23-45-67-89-AB',
+        '01-23-45-67-89-ab',
+        '0123456789AB',
+        '0123456789ab',
+    ]
+    schema = vol.Schema(cv.is_mac_address)
+    for mac in test_2_chunk:
+        schema(mac)
+
+    test_4_chunk = [
+        '0123:4567:89AB',
+        '0123:4567:89ab',
+        '0123.4567.89AB',
+        '0123.4567.89ab',
+        '0123-4567-89AB',
+        '0123-4567-89ab',
+        '0123456789AB',
+        '0123456789ab',
+    ]
+    schema = vol.Schema(cv.is_mac_address(chunk=4))
+    for mac in test_4_chunk:
+        schema(mac)
+
+    test_6_chunk = [
+        '012345:6789AB',
+        '012345:6789ab',
+        '012345.6789AB',
+        '012345.6789ab',
+        '012345-6789AB',
+        '012345-6789ab',
+        '0123456789AB',
+        '0123456789ab',
+    ]
+    schema = vol.Schema(cv.is_mac_address(chunk=6))
+    for mac in test_6_chunk:
+        schema(mac)