diff --git a/planet/auth.py b/planet/auth.py
index 4730128..8540053 100644
--- a/planet/auth.py
+++ b/planet/auth.py
@@ -27,7 +27,7 @@ from .exceptions import AuthException
 
 LOGGER = logging.getLogger(__name__)
 
-BASE_URL = constants.PLANET_BASE_URL
+BASE_URL = constants.PLANET_BASE_URL + 'v0/auth/'
 ENV_API_KEY = 'PL_API_KEY'
 SECRET_FILE_PATH = os.path.join(os.path.expanduser('~'), '.planet.json')
 
@@ -161,8 +161,6 @@ class AuthClient():
         if not self._base_url.endswith('/'):
             self._base_url += '/'
 
-        self._auth_url = self._base_url + 'v0/auth/'
-
     def login(
         self,
         email: str,
@@ -181,7 +179,7 @@ class AuthClient():
              A JSON object containing an `api_key` property with the user's
         API_KEY.
         '''
-        url = self._auth_url + 'login'
+        url = self._base_url + 'login'
         data = {'email': email,
                 'password': password
                 }

diff --git a/tests/integration/test_auth_api.py b/tests/integration/test_auth_api.py
index a23510d..0a6e532 100644
--- a/tests/integration/test_auth_api.py
+++ b/tests/integration/test_auth_api.py
@@ -1,4 +1,4 @@
-# Copyright 2021 Planet Labs, Inc.
+# Copyright 2021 Planet Labs, PBC.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may not
 # use this file except in compliance with the License. You may obtain a copy of
@@ -24,14 +24,13 @@ from planet.auth import AuthClient
 
 
 TEST_URL = 'http://MockNotRealURL/'
-AUTH_URL = TEST_URL + 'v0/auth/'
 
 LOGGER = logging.getLogger(__name__)
 
 
 @respx.mock
 def test_AuthClient_success():
-    login_url = AUTH_URL + 'login'
+    login_url = TEST_URL + 'login'
 
     payload = {'api_key': 'iamakey'}
     resp = {'token': jwt.encode(payload, 'key')}
@@ -46,7 +45,7 @@ def test_AuthClient_success():
 
 @respx.mock
 def test_AuthClient_invalid_email():
-    login_url = AUTH_URL + 'login'
+    login_url = TEST_URL + 'login'
 
     resp = {
         "errors": {
@@ -69,7 +68,7 @@ def test_AuthClient_invalid_email():
 
 @respx.mock
 def test_AuthClient_invalid_password():
-    login_url = AUTH_URL + 'login'
+    login_url = TEST_URL + 'login'
 
     resp = {
         "errors": None,
diff --git a/tests/integration/test_auth_cli.py b/tests/integration/test_auth_cli.py
new file mode 100644
index 0000000..02a57f0
--- /dev/null
+++ b/tests/integration/test_auth_cli.py
@@ -0,0 +1,55 @@
+# Copyright 2022 Planet Labs, PBC.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+from http import HTTPStatus
+from unittest.mock import MagicMock
+
+from click.testing import CliRunner
+import httpx
+import jwt
+import pytest
+import respx
+
+import planet
+from planet.cli import cli
+
+TEST_URL = 'http://MockNotRealURL/'
+
+
+@pytest.fixture(autouse=True)
+def patch_session(monkeypatch):
+    '''Make sure we don't actually make any http calls'''
+    monkeypatch.setattr(planet, 'Session', MagicMock(spec=planet.Session))
+
+
+@respx.mock
+@pytest.mark.asyncio
+def test_cli_auth_init_base_url():
+    '''Test base url option
+
+    Uses the auth init path to ensure the base url is changed to the mocked
+    url. So, ends up testing the auth init path somewhat as well
+    '''
+    login_url = TEST_URL + 'login'
+
+    payload = {'api_key': 'iamakey'}
+    resp = {'token': jwt.encode(payload, 'key')}
+    mock_resp = httpx.Response(HTTPStatus.OK, json=resp)
+    respx.post(login_url).return_value = mock_resp
+
+    result = CliRunner().invoke(
+        cli.main,
+        args=['auth', '--base-url', TEST_URL, 'init'],
+        input='email\npw\n')
+
+    assert not result.exception

change auth base url to the api url
The orders client base url points to the orders API endpoint. Changing the base url replaces the entire url path. Right now, the auth client base url is just the root url, and the relative path to the auth API endpoint is added in the client. Changing the base url only changes the root url. Bring the functionality of the auth client (and, therefore, auth CLI) into alignment with the functionality of the orders api: that is, change the auth base url to the api endpoint.
tests/integration/test_auth_api.py::test_AuthClient_success tests/integration/test_auth_api.py::test_AuthClient_invalid_email tests/integration/test_auth_api.py::test_AuthClient_invalid_password tests/integration/test_auth_cli.py::test_cli_auth_init_base_url