diff --git a/testing/mozbase/mozfile/setup.py b/testing/mozbase/mozfile/setup.py
index 172df3e68e47..34c31e10854f 100644
--- a/testing/mozbase/mozfile/setup.py
+++ b/testing/mozbase/mozfile/setup.py
@@ -29,6 +29,6 @@ setup(
     packages=["mozfile"],
     include_package_data=True,
     zip_safe=False,
-    install_requires=["six >= 1.13.0"],
+    install_requires=[],
     tests_require=["wptserve"],
 )
diff --git a/tools/browsertime/mach_commands.py b/tools/browsertime/mach_commands.py
index 5627b95fc314..53ba58d37d67 100644
--- a/tools/browsertime/mach_commands.py
+++ b/tools/browsertime/mach_commands.py
@@ -40,12 +40,12 @@ import stat
 import subprocess
 import sys
 import time
+from io import StringIO
 
 import mozpack.path as mozpath
 from mach.decorators import Command, CommandArgument
 from mozbuild.base import BinaryNotFoundException, MachCommandBase
 from mozbuild.dirutils import mkdir
-from six import StringIO
 
 AUTOMATION = "MOZ_AUTOMATION" in os.environ
 BROWSERTIME_ROOT = os.path.dirname(__file__)
diff --git a/tools/lint/hooks_clang_format.py b/tools/lint/hooks_clang_format.py
index 31fd502f5280..0d93640b3c38 100755
--- a/tools/lint/hooks_clang_format.py
+++ b/tools/lint/hooks_clang_format.py
@@ -13,11 +13,9 @@ topsrcdir = os.path.join(here, os.pardir, os.pardir)
 
 EXTRA_PATHS = (
     "python/mach",
-    "python/mozbuild",
     "python/mozversioncontrol",
     "testing/mozbase/mozfile",
     "third_party/python/jsmin",
-    "third_party/python/six",
 )
 sys.path[:0] = [os.path.join(topsrcdir, p) for p in EXTRA_PATHS]
 
diff --git a/tools/tryselect/selectors/coverage.py b/tools/tryselect/selectors/coverage.py
index e98bc69078bc..1da87a45f572 100644
--- a/tools/tryselect/selectors/coverage.py
+++ b/tools/tryselect/selectors/coverage.py
@@ -13,7 +13,6 @@ import sqlite3
 import subprocess
 
 import requests
-import six
 from mach.util import get_state_dir
 from mozbuild.base import MozbuildObject
 from mozpack.files import FileFinder
@@ -37,9 +36,10 @@ def setup_globals():
     build = MozbuildObject.from_environment(cwd=here)
     vcs = get_repository_object(build.topsrcdir)
 
-    root_hash = hashlib.sha256(
-        six.ensure_binary(os.path.abspath(build.topsrcdir))
-    ).hexdigest()
+    topsrcdir = build.topsrcdir
+    if isinstance(topsrcdir, str):
+        topsrcdir = topsrcdir.encode()
+    root_hash = hashlib.sha256(os.path.abspath(topsrcdir)).hexdigest()
     cache_dir = os.path.join(get_state_dir(), "cache", root_hash, "chunk_mapping")
     if not os.path.isdir(cache_dir):
         os.makedirs(cache_dir)
@@ -421,11 +421,7 @@ def run(
     print("Found " + test_count_message)
 
     # Set the test paths to be run by setting MOZHARNESS_TEST_PATHS.
-    path_env = {
-        "MOZHARNESS_TEST_PATHS": six.ensure_text(
-            json.dumps(resolve_tests_by_suite(test_files))
-        )
-    }
+    path_env = {"MOZHARNESS_TEST_PATHS": json.dumps(resolve_tests_by_suite(test_files))}
     try_config_params.setdefault("try_task_config", {}).setdefault("env", {}).update(
         path_env
     )
diff --git a/tools/tryselect/task_config.py b/tools/tryselect/task_config.py
index 35451a7726bc..6d796707f671 100644
--- a/tools/tryselect/task_config.py
+++ b/tools/tryselect/task_config.py
@@ -18,7 +18,6 @@ from textwrap import dedent
 
 import mozpack.path as mozpath
 import requests
-import six
 from mozbuild.base import BuildEnvironmentNotFoundException, MozbuildObject
 from taskgraph.util import taskcluster
 
@@ -224,9 +223,7 @@ class Path(TryConfig):
         ]
         return {
             "env": {
-                "MOZHARNESS_TEST_PATHS": six.ensure_text(
-                    json.dumps(resolve_tests_by_suite(paths))
-                ),
+                "MOZHARNESS_TEST_PATHS": json.dumps(resolve_tests_by_suite(paths)),
             }
         }
 
diff --git a/tools/tryselect/test/test_again.py b/tools/tryselect/test/test_again.py
index 7aa516369db5..abe914e89a12 100644
--- a/tools/tryselect/test/test_again.py
+++ b/tools/tryselect/test/test_again.py
@@ -3,10 +3,10 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os
+from importlib import reload
 
 import mozunit
 import pytest
-from six.moves import reload_module as reload
 from tryselect import push
 from tryselect.selectors import again
 
diff --git a/tools/tryselect/util/fzf.py b/tools/tryselect/util/fzf.py
index 296d185c102a..78e5a6c5afbb 100644
--- a/tools/tryselect/util/fzf.py
+++ b/tools/tryselect/util/fzf.py
@@ -10,7 +10,6 @@ import subprocess
 import sys
 
 import mozfile
-import six
 from gecko_taskgraph.target_tasks import filter_by_uncommon_try_tasks
 from mach.util import get_state_dir
 from mozboot.util import http_download_and_save
@@ -239,7 +238,7 @@ def get_fzf_version(fzf_bin):
         sys.exit(1)
 
     # Some fzf versions have extra, e.g 0.18.0 (ff95134)
-    fzf_version = six.ensure_text(fzf_version.split()[0])
+    fzf_version = fzf_version.split()[0].decode()
 
     return fzf_version
 
diff --git a/tools/tryselect/util/manage_estimates.py b/tools/tryselect/util/manage_estimates.py
index 9a73e8324fa2..bf652efa83ae 100644
--- a/tools/tryselect/util/manage_estimates.py
+++ b/tools/tryselect/util/manage_estimates.py
@@ -8,7 +8,6 @@ import os
 from datetime import datetime, timedelta
 
 import requests
-import six
 
 TASK_DURATION_URL = (
     "https://storage.googleapis.com/mozilla-mach-data/task_duration_history.json"
@@ -96,7 +95,7 @@ def download_task_history_data(cache_dir):
         return
 
     with open(graph_quantile_cache, "w") as f:
-        f.write(six.ensure_text(r.content))
+        f.write(r.text)
 
     with open(task_duration_tag_file, "w") as f:
         json.dump({"download_date": datetime.now().strftime("%Y-%m-%d")}, f, indent=4)