diff --git a/google/cloud/ndb/_gql.py b/google/cloud/ndb/_gql.py
index 2d0a2745..676db168 100644
--- a/google/cloud/ndb/_gql.py
+++ b/google/cloud/ndb/_gql.py
@@ -1,6 +1,5 @@
 import datetime
 import re
-import six
 import time
 
 from google.cloud.ndb import context as context_module
@@ -650,7 +649,7 @@ def _args_to_val(self, func, args):
         """
         vals = []
         for arg in args:
-            if isinstance(arg, six.string_types + six.integer_types):
+            if isinstance(arg, (str, int)):
                 val = query_module.Parameter(arg)
             else:
                 val = arg.Get()
@@ -774,7 +773,7 @@ def _raise_cast_error(message):
 def _time_function(values):
     if len(values) == 1:
         value = values[0]
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             try:
                 time_tuple = time.strptime(value, "%H:%M:%S")
             except ValueError as error:
@@ -783,7 +782,7 @@ def _time_function(values):
                 )
             time_tuple = time_tuple[3:]
             time_tuple = time_tuple[0:3]
-        elif isinstance(value, six.integer_types):
+        elif isinstance(value, int):
             time_tuple = (value,)
         else:
             _raise_cast_error("Invalid argument for time(), {}".format(value))
@@ -800,7 +799,7 @@ def _time_function(values):
 def _date_function(values):
     if len(values) == 1:
         value = values[0]
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             try:
                 time_tuple = time.strptime(value, "%Y-%m-%d")[0:6]
             except ValueError as error:
@@ -822,7 +821,7 @@ def _date_function(values):
 def _datetime_function(values):
     if len(values) == 1:
         value = values[0]
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             try:
                 time_tuple = time.strptime(value, "%Y-%m-%d %H:%M:%S")[0:6]
             except ValueError as error:
diff --git a/google/cloud/ndb/context.py b/google/cloud/ndb/context.py
index ff347660..90a39917 100644
--- a/google/cloud/ndb/context.py
+++ b/google/cloud/ndb/context.py
@@ -20,7 +20,6 @@
 import contextvars
 import itertools
 import os
-import six
 import threading
 import uuid
 
@@ -550,7 +549,7 @@ def set_global_cache_timeout_policy(self, policy):
         if policy is None:
             policy = _default_global_cache_timeout_policy
 
-        elif isinstance(policy, six.integer_types):
+        elif isinstance(policy, int):
             timeout = policy
 
             def policy(key):
diff --git a/google/cloud/ndb/key.py b/google/cloud/ndb/key.py
index 04b1c1ff..7252f9e2 100644
--- a/google/cloud/ndb/key.py
+++ b/google/cloud/ndb/key.py
@@ -90,7 +90,6 @@
 
 import base64
 import functools
-import six
 
 from google.cloud.datastore import _app_engine_key_pb2
 from google.cloud.datastore import key as _key_module
@@ -1245,7 +1244,7 @@ def _from_urlsafe(urlsafe, app, namespace, database):
         Tuple[google.cloud.datastore.key.Key, .Reference]: The key
         corresponding to ``urlsafe`` and the Reference protobuf.
     """
-    if isinstance(urlsafe, six.string_types):  # pragma: NO BRANCH
+    if isinstance(urlsafe, str):  # pragma: NO BRANCH
         urlsafe = urlsafe.encode("ascii")
     padding = b"=" * (-len(urlsafe) % 4)
     urlsafe += padding
@@ -1526,7 +1525,7 @@ def _clean_flat_path(flat):
         if isinstance(kind, type):
             kind = kind._get_kind()
             flat[i] = kind
-        if not isinstance(kind, six.string_types):
+        if not isinstance(kind, str):
             raise TypeError(
                 "Key kind must be a string or Model class; "
                 "received {!r}".format(kind)
@@ -1537,7 +1536,7 @@ def _clean_flat_path(flat):
         if id_ is None:
             if i + 2 < len(flat):
                 raise exceptions.BadArgumentError("Incomplete Key entry must be last")
-        elif not isinstance(id_, six.string_types + six.integer_types):
+        elif not isinstance(id_, (str, int)):
             raise TypeError(_INVALID_ID_TYPE.format(id_))
 
     # Remove trailing ``None`` for a partial key.
diff --git a/google/cloud/ndb/model.py b/google/cloud/ndb/model.py
index 51d082f7..8073bb44 100644
--- a/google/cloud/ndb/model.py
+++ b/google/cloud/ndb/model.py
@@ -257,7 +257,6 @@ class Person(Model):
 import inspect
 import json
 import pickle
-import six
 import zlib
 
 import pytz
@@ -1069,7 +1068,7 @@ def _verify_name(name):
             TypeError: If the ``name`` is not a string.
             ValueError: If the name contains a ``.``.
         """
-        if not isinstance(name, six.string_types):
+        if not isinstance(name, str):
             raise TypeError("Name {!r} is not a string".format(name))
 
         if "." in name:
@@ -2087,7 +2086,7 @@ def _legacy_db_get_value(v, p):
                     # If this passes, don't return unicode.
                 except UnicodeDecodeError:
                     try:
-                        sval = six.text_type(sval.decode("utf-8"))
+                        sval = str(sval.decode("utf-8"))
                     except UnicodeDecodeError:
                         pass
             return sval
@@ -2420,7 +2419,7 @@ def _validate(self, value):
             .BadValueError: If ``value`` is not an :class:`int` or convertible
                 to one.
         """
-        if not isinstance(value, six.integer_types):
+        if not isinstance(value, int):
             raise exceptions.BadValueError(
                 "In field {}, expected integer, got {!r}".format(self._name, value)
             )
@@ -2452,14 +2451,14 @@ def _validate(self, value):
             .BadValueError: If ``value`` is not a :class:`float` or convertible
                 to one.
         """
-        if not isinstance(value, six.integer_types + (float,)):
+        if not isinstance(value, (float, int)):
             raise exceptions.BadValueError(
                 "In field {}, expected float, got {!r}".format(self._name, value)
             )
         return float(value)
 
 
-class _CompressedValue(six.binary_type):
+class _CompressedValue(bytes):
     """A marker object wrapping compressed values.
 
     Args:
@@ -2769,7 +2768,7 @@ def _validate(self, value):
             .BadValueError: If the current property is indexed but the UTF-8
                 encoded value exceeds the maximum length (1500 bytes).
         """
-        if not isinstance(value, six.text_type):
+        if not isinstance(value, str):
             # In Python 2.7, bytes is a synonym for str
             if isinstance(value, bytes):
                 try:
@@ -2796,7 +2795,7 @@ def _to_base_type(self, value):
             :class:`str`, this will return the UTF-8 encoded bytes for it.
             Otherwise, it will return :data:`None`.
         """
-        if isinstance(value, six.text_type):
+        if isinstance(value, str):
             return value.encode("utf-8")
 
     def _from_base_type(self, value):
@@ -2931,7 +2930,7 @@ def _validate(self, value):
             .BadValueError: If the current property is indexed but the UTF-8
                 encoded value exceeds the maximum length (1500 bytes).
         """
-        if isinstance(value, six.binary_type):
+        if isinstance(value, bytes):
             try:
                 encoded_length = len(value)
                 value = value.decode("utf-8")
@@ -2941,7 +2940,7 @@ def _validate(self, value):
                         self._name, value
                     )
                 )
-        elif isinstance(value, six.string_types):
+        elif isinstance(value, str):
             encoded_length = len(value.encode("utf-8"))
         else:
             raise exceptions.BadValueError("Expected string, got {!r}".format(value))
@@ -2963,7 +2962,7 @@ def _to_base_type(self, value):
             :class:`bytes`, this will return the UTF-8 decoded ``str`` for it.
             Otherwise, it will return :data:`None`.
         """
-        if isinstance(value, six.binary_type):
+        if isinstance(value, bytes):
             return value.decode("utf-8")
 
     def _from_base_type(self, value):
@@ -2986,7 +2985,7 @@ def _from_base_type(self, value):
             :class:`str` corresponding to it. Otherwise, it will return
             :data:`None`.
         """
-        if isinstance(value, six.binary_type):
+        if isinstance(value, bytes):
             try:
                 return value.decode("utf-8")
             except UnicodeError:
@@ -3194,7 +3193,7 @@ def _from_base_type(self, value):
         """
         # We write and retrieve `bytes` normally, but for some reason get back
         # `str` from a projection query.
-        if not isinstance(value, six.text_type):
+        if not isinstance(value, str):
             value = value.decode("ascii")
         return json.loads(value)
 
@@ -3495,14 +3494,14 @@ def _to_base_type(self, value):
         user_entity = ds_entity_module.Entity()
 
         # Set required fields.
-        user_entity["email"] = six.ensure_text(value.email())
+        user_entity["email"] = str(value.email())
         user_entity.exclude_from_indexes.add("email")
-        user_entity["auth_domain"] = six.ensure_text(value.auth_domain())
+        user_entity["auth_domain"] = str(value.auth_domain())
         user_entity.exclude_from_indexes.add("auth_domain")
         # Set optional field.
         user_id = value.user_id()
         if user_id:
-            user_entity["user_id"] = six.ensure_text(user_id)
+            user_entity["user_id"] = str(user_id)
             user_entity.exclude_from_indexes.add("user_id")
 
         return user_entity
@@ -3597,7 +3596,7 @@ def _handle_positional(wrapped):
         @functools.wraps(wrapped)
         def wrapper(self, *args, **kwargs):
             for arg in args:
-                if isinstance(arg, six.string_types):
+                if isinstance(arg, str):
                     if "name" in kwargs:
                         raise TypeError("You can only specify name once")
 
@@ -3636,7 +3635,7 @@ def __init__(
             kind = kind._get_kind()
 
         else:
-            if kind is not None and not isinstance(kind, six.string_types):
+            if kind is not None and not isinstance(kind, str):
                 raise TypeError("Kind must be a Model class or a string")
 
         super(KeyProperty, self).__init__(
@@ -3918,7 +3917,7 @@ def _from_base_type(self, value):
                 returns the value without ``tzinfo`` or ``None`` if value did
                 not have ``tzinfo`` set.
         """
-        if isinstance(value, six.integer_types):
+        if isinstance(value, int):
             # Projection query, value is integer nanoseconds
             seconds = value / 1e6
             value = datetime.datetime.fromtimestamp(seconds, pytz.utc)
@@ -4683,8 +4682,7 @@ def __repr__(cls):
         return "{}<{}>".format(cls.__name__, ", ".join(props))
 
 
-@six.add_metaclass(MetaModel)
-class Model(_NotEqualMixin):
+class Model(_NotEqualMixin, metaclass=MetaModel):
     """A class describing Cloud Datastore entities.
 
     Model instances are usually called entities. All model classes
@@ -4950,7 +4948,7 @@ def __init__(_self, **kwargs):
 
     def _get_property_for(self, p, indexed=True, depth=0):
         """Internal helper to get the Property for a protobuf-level property."""
-        if isinstance(p.name(), six.text_type):
+        if isinstance(p.name(), str):
             p.set_name(bytes(p.name(), encoding="utf-8"))
         parts = p.name().decode().split(".")
         if len(parts) <= depth:
@@ -5008,9 +5006,9 @@ def _from_pb(cls, pb, set_key=True, ent=None, key=None):
         # A key passed in overrides a key in the pb.
         if key is None and pb.key().path.element_size():
             # modern NDB expects strings.
-            if not isinstance(pb.key_.app_, six.text_type):  # pragma: NO BRANCH
+            if not isinstance(pb.key_.app_, str):  # pragma: NO BRANCH
                 pb.key_.app_ = pb.key_.app_.decode()
-            if not isinstance(pb.key_.name_space_, six.text_type):  # pragma: NO BRANCH
+            if not isinstance(pb.key_.name_space_, str):  # pragma: NO BRANCH
                 pb.key_.name_space_ = pb.key_.name_space_.decode()
 
             key = Key(reference=pb.key())
@@ -5316,7 +5314,7 @@ def _fix_up_properties(cls):
                 an underscore.
         """
         kind = cls._get_kind()
-        if not isinstance(kind, six.string_types):
+        if not isinstance(kind, str):
             raise KindError(
                 "Class {} defines a ``_get_kind()`` method that returns "
                 "a non-string ({!r})".format(cls.__name__, kind)
@@ -6046,7 +6044,7 @@ def _get_or_insert_async(_cls, _name, *args, **kwargs):
         project = _cls._get_arg(kwargs, "project")
         options = kwargs.pop("_options")
 
-        if not isinstance(name, six.string_types):
+        if not isinstance(name, str):
             raise TypeError("'name' must be a string; received {!r}".format(name))
 
         elif not name:
@@ -6651,10 +6649,10 @@ def get_indexes(**options):
 def _unpack_user(v):
     """Internal helper to unpack a User value from a protocol buffer."""
     uv = v.uservalue()
-    email = six.text_type(uv.email().decode("utf-8"))
-    auth_domain = six.text_type(uv.auth_domain().decode("utf-8"))
+    email = str(uv.email().decode("utf-8"))
+    auth_domain = str(uv.auth_domain().decode("utf-8"))
     obfuscated_gaiaid = uv.obfuscated_gaiaid().decode("utf-8")
-    obfuscated_gaiaid = six.text_type(obfuscated_gaiaid)
+    obfuscated_gaiaid = str(obfuscated_gaiaid)
 
     value = User(
         email=email,
diff --git a/google/cloud/ndb/query.py b/google/cloud/ndb/query.py
index 6109fe11..232e9dab 100644
--- a/google/cloud/ndb/query.py
+++ b/google/cloud/ndb/query.py
@@ -139,7 +139,6 @@ def ranked(cls, rank):
 
 import functools
 import logging
-import six
 
 from google.cloud.ndb import context as context_module
 from google.cloud.ndb import exceptions
@@ -305,7 +304,7 @@ class Parameter(ParameterizedThing):
     """
 
     def __init__(self, key):
-        if not isinstance(key, six.integer_types + six.string_types):
+        if not isinstance(key, (int, str)):
             raise TypeError(
                 "Parameter key must be an integer or string, not {}".format(key)
             )
@@ -1677,7 +1676,7 @@ def _to_property_orders(self, order_by):
             elif isinstance(order, model.Property):
                 # use the sign to turn it into a PropertyOrder
                 orders.append(+order)
-            elif isinstance(order, six.string_types):
+            elif isinstance(order, str):
                 name = order
                 reverse = False
                 if order.startswith("-"):
@@ -2346,7 +2345,7 @@ def _to_property_names(properties):
 
     fixed = []
     for prop in properties:
-        if isinstance(prop, six.string_types):
+        if isinstance(prop, str):
             fixed.append(prop)
         elif isinstance(prop, model.Property):
             fixed.append(prop._name)
diff --git a/setup.py b/setup.py
index d5c32763..c67787af 100644
--- a/setup.py
+++ b/setup.py
@@ -46,8 +46,6 @@ def main():
         "pymemcache >= 2.1.0, < 5.0.0dev",
         "pytz >= 2018.3",
         "redis >= 3.0.0, < 6.0.0dev",
-        # TODO(https://github.com/googleapis/python-ndb/issues/913) remove this dependency once six is no longer used in the codebase
-        "six >= 1.12.0, < 2.0.0dev"
     ]
 
     setuptools.setup(