diff --git a/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag b/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
index e3da831f3c..393554a9f2 100755
--- a/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
+++ b/puppet/zulip/files/nagios_plugins/zulip_postgresql/check_postgresql_replication_lag
@@ -57,9 +57,7 @@ def run_sql_query(query: str) -> List[List[str]]:
         f"SELECT {query}",
     ]
     try:
-        output = subprocess.check_output(
-            command, stderr=subprocess.STDOUT, universal_newlines=True
-        ).strip()
+        output = subprocess.check_output(command, stderr=subprocess.STDOUT, text=True).strip()
         if not output:
             return []
         return [x.split("\0") for x in output.split("\n")]
diff --git a/puppet/zulip/files/postgresql/pg_backup_and_purge b/puppet/zulip/files/postgresql/pg_backup_and_purge
index 989987a9cc..9af5b7b432 100755
--- a/puppet/zulip/files/postgresql/pg_backup_and_purge
+++ b/puppet/zulip/files/postgresql/pg_backup_and_purge
@@ -21,7 +21,7 @@ def run(args: List[str], dry_run: bool = False) -> str:
         print("Would have run: " + " ".join(map(shlex.quote, args)))
         return ""
 
-    return subprocess.check_output(args, stdin=subprocess.DEVNULL, universal_newlines=True)
+    return subprocess.check_output(args, stdin=subprocess.DEVNULL, text=True)
 
 
 recovery_val = run(
diff --git a/scripts/lib/check_rabbitmq_queue.py b/scripts/lib/check_rabbitmq_queue.py
index cae5b05f11..619ea6e4e8 100644
--- a/scripts/lib/check_rabbitmq_queue.py
+++ b/scripts/lib/check_rabbitmq_queue.py
@@ -134,7 +134,7 @@ def check_rabbitmq_queues() -> None:
 
     list_queues_output = subprocess.check_output(
         ["/usr/sbin/rabbitmqctl", "list_queues", "name", "messages", "consumers"],
-        universal_newlines=True,
+        text=True,
     )
     queue_counts_rabbitmqctl = {}
     queues_with_consumers = []
@@ -151,7 +151,7 @@ def check_rabbitmq_queues() -> None:
 
     queue_stats_dir = subprocess.check_output(
         [os.path.join(ZULIP_PATH, "scripts/get-django-setting"), "QUEUE_STATS_DIR"],
-        universal_newlines=True,
+        text=True,
     ).strip()
     queue_stats: Dict[str, Dict[str, Any]] = {}
     queues_to_check = set(normal_queues).intersection(set(queues_with_consumers))
diff --git a/scripts/lib/hash_reqs.py b/scripts/lib/hash_reqs.py
index 4d7c4b2641..87a3995503 100755
--- a/scripts/lib/hash_reqs.py
+++ b/scripts/lib/hash_reqs.py
@@ -35,7 +35,7 @@ def python_version() -> str:
     """
     Returns the Python version as string 'Python major.minor.patchlevel'
     """
-    return subprocess.check_output(["/usr/bin/python3", "-VV"], universal_newlines=True)
+    return subprocess.check_output(["/usr/bin/python3", "-VV"], text=True)
 
 
 def hash_deps(deps: Iterable[str]) -> str:
diff --git a/scripts/lib/node_cache.py b/scripts/lib/node_cache.py
index 1ae3835e93..afd6cfca7e 100644
--- a/scripts/lib/node_cache.py
+++ b/scripts/lib/node_cache.py
@@ -42,9 +42,7 @@ def generate_sha1sum_node_modules(
             data[YARN_LOCK_FILE_PATH] = f.read().strip()
     with open(YARN_PACKAGE_JSON) as f:
         data["yarn-package-version"] = json.load(f)["version"]
-    data["node-version"] = subprocess.check_output(
-        ["node", "--version"], universal_newlines=True
-    ).strip()
+    data["node-version"] = subprocess.check_output(["node", "--version"], text=True).strip()
     data["yarn-args"] = get_yarn_args(production=production)
 
     sha1sum = hashlib.sha1()
diff --git a/scripts/lib/puppet_cache.py b/scripts/lib/puppet_cache.py
index 5abe00bef0..1e85c4994b 100644
--- a/scripts/lib/puppet_cache.py
+++ b/scripts/lib/puppet_cache.py
@@ -23,7 +23,7 @@ def generate_sha1sum_puppet_modules() -> str:
     data["puppet-version"] = subprocess.check_output(
         # This is 10x faster than `puppet --version`
         ["ruby", "-r", "puppet/version", "-e", "puts Puppet.version"],
-        universal_newlines=True,
+        text=True,
     ).strip()
 
     sha1sum = hashlib.sha1()
diff --git a/scripts/lib/setup_venv.py b/scripts/lib/setup_venv.py
index 4c77366045..ad5ebd66d7 100644
--- a/scripts/lib/setup_venv.py
+++ b/scripts/lib/setup_venv.py
@@ -178,9 +178,7 @@ def try_to_copy_venv(venv_path: str, new_packages: Set[str]) -> bool:
         venv_python3 = os.path.join(curr_venv_path, "bin", "python3")
         if not os.path.exists(venv_python3):
             continue
-        venv_python_version = subprocess.check_output(
-            [venv_python3, "-VV"], universal_newlines=True
-        )
+        venv_python_version = subprocess.check_output([venv_python3, "-VV"], text=True)
         if desired_python_version != venv_python_version:
             continue
 
@@ -282,7 +280,7 @@ def do_patch_activate_script(venv_path: str) -> None:
 
 def generate_hash(requirements_file: str) -> str:
     path = os.path.join(ZULIP_PATH, "scripts", "lib", "hash_reqs.py")
-    output = subprocess.check_output([path, requirements_file], universal_newlines=True)
+    output = subprocess.check_output([path, requirements_file], text=True)
     return output.split()[0]
 
 
diff --git a/scripts/lib/sharding.py b/scripts/lib/sharding.py
index 65b7b34fc1..127a9aa9d3 100755
--- a/scripts/lib/sharding.py
+++ b/scripts/lib/sharding.py
@@ -53,7 +53,7 @@ def write_updated_configs() -> None:
         shard_map: Dict[str, int] = {}
         external_host = subprocess.check_output(
             [os.path.join(BASE_DIR, "scripts/get-django-setting"), "EXTERNAL_HOST"],
-            universal_newlines=True,
+            text=True,
         ).strip()
         for port in config_file["tornado_sharding"]:
             shards = config_file["tornado_sharding"][port].strip()
diff --git a/scripts/lib/upgrade-zulip b/scripts/lib/upgrade-zulip
index fbf108b976..4cf8d44056 100755
--- a/scripts/lib/upgrade-zulip
+++ b/scripts/lib/upgrade-zulip
@@ -54,7 +54,7 @@ try:
     logging.info("Unpacking the tarball")
     unpack_zulip = os.path.realpath(os.path.join(os.path.dirname(__file__), "unpack-zulip"))
     deploy_path = subprocess.check_output(
-        [unpack_zulip, archived_tarball_path], preexec_fn=su_to_zulip, universal_newlines=True
+        [unpack_zulip, archived_tarball_path], preexec_fn=su_to_zulip, text=True
     )
 
     # Chdir to deploy_path and then run upgrade-zulip-stage-2 from the
diff --git a/scripts/lib/upgrade-zulip-stage-2 b/scripts/lib/upgrade-zulip-stage-2
index d866e80096..693900b269 100755
--- a/scripts/lib/upgrade-zulip-stage-2
+++ b/scripts/lib/upgrade-zulip-stage-2
@@ -263,7 +263,7 @@ migrations_needed = False
 if not args.skip_migrations:
     logging.info("Checking for needed migrations")
     migrations_output = subprocess.check_output(
-        ["./manage.py", "showmigrations"], preexec_fn=su_to_zulip, universal_newlines=True
+        ["./manage.py", "showmigrations"], preexec_fn=su_to_zulip, text=True
     )
     need_create_large_indexes = False
     for ln in migrations_output.split("\n"):
diff --git a/scripts/lib/zulip_tools.py b/scripts/lib/zulip_tools.py
index 2ad4cbeaa2..18274303f5 100755
--- a/scripts/lib/zulip_tools.py
+++ b/scripts/lib/zulip_tools.py
@@ -620,7 +620,7 @@ def has_application_server(once: bool = False) -> bool:
 def list_supervisor_processes(*args: str) -> List[str]:
     worker_status = subprocess.run(
         ["supervisorctl", "status", *args],
-        universal_newlines=True,
+        text=True,
         stdout=subprocess.PIPE,
     )
     # `supervisorctl status` returns 3 if any are stopped, which is
diff --git a/scripts/nagios/check-rabbitmq-consumers b/scripts/nagios/check-rabbitmq-consumers
index b579c7a127..ed0e42b156 100755
--- a/scripts/nagios/check-rabbitmq-consumers
+++ b/scripts/nagios/check-rabbitmq-consumers
@@ -33,9 +33,7 @@ options = parser.parse_args()
 config_file = get_config_file()
 TORNADO_PROCESSES = len(get_tornado_ports(config_file))
 
-output = subprocess.check_output(
-    ["/usr/sbin/rabbitmqctl", "list_consumers"], universal_newlines=True
-)
+output = subprocess.check_output(["/usr/sbin/rabbitmqctl", "list_consumers"], text=True)
 
 consumers: Dict[str, int] = defaultdict(int)
 
diff --git a/scripts/setup/restore-backup b/scripts/setup/restore-backup
index 642b4840db..c9d8a1bdae 100755
--- a/scripts/setup/restore-backup
+++ b/scripts/setup/restore-backup
@@ -124,7 +124,7 @@ def restore_backup(tarball_file: IO[bytes]) -> None:
                     os.path.join(settings.DEPLOY_ROOT, "scripts", "get-django-setting"),
                     "RABBITMQ_HOST",
                 ],
-                universal_newlines=True,
+                text=True,
             ).strip()
             if rabbitmq_host in ["127.0.0.1", "::1", "localhost", "localhost6"]:
                 run([os.path.join(settings.DEPLOY_ROOT, "scripts", "setup", "configure-rabbitmq")])
diff --git a/tools/diagnose b/tools/diagnose
index ae125dc970..e992db50a2 100755
--- a/tools/diagnose
+++ b/tools/diagnose
@@ -114,7 +114,7 @@ def check_venv() -> bool:
     cache_dir = "/srv/zulip-venv-cache/"
     for fn in ["dev.txt"]:
         requirements_file = os.path.join(ROOT_DIR, "requirements", fn)
-        output = subprocess.check_output([path, requirements_file], universal_newlines=True)
+        output = subprocess.check_output([path, requirements_file], text=True)
         sha1sum = output.split()[0]
         print(fn, "venv sha: ", sha1sum)
         if not os.path.exists(os.path.join(cache_dir, sha1sum)):
diff --git a/tools/i18n/process-mobile-i18n b/tools/i18n/process-mobile-i18n
index d593ccc7d5..64b43a5167 100755
--- a/tools/i18n/process-mobile-i18n
+++ b/tools/i18n/process-mobile-i18n
@@ -11,7 +11,7 @@ def get_json_filename(locale: str) -> str:
 
 
 def get_locales() -> List[str]:
-    output = check_output(["git", "ls-files", "locale"], universal_newlines=True)
+    output = check_output(["git", "ls-files", "locale"], text=True)
     tracked_files = output.split()
     regex = re.compile(r"locale/(\w+)/LC_MESSAGES/django.po")
     locales = ["en"]
diff --git a/tools/lib/pretty_print.py b/tools/lib/pretty_print.py
index daa564d43a..1691248cb6 100644
--- a/tools/lib/pretty_print.py
+++ b/tools/lib/pretty_print.py
@@ -177,7 +177,7 @@ Proposed {BOLDRED}diff{ENDC} for {CYAN}{fn}{ENDC}:
             """,
             flush=True,
         )
-        subprocess.run(["diff", fn, "-"], input=phtml, universal_newlines=True)
+        subprocess.run(["diff", fn, "-"], input=phtml, text=True)
         print(
             f"""
 ---
diff --git a/tools/review b/tools/review
index 98b5540b60..820c0e37d6 100755
--- a/tools/review
+++ b/tools/review
@@ -17,7 +17,7 @@ def run(command: List[str]) -> None:
 
 
 def check_output(command: List[str]) -> str:
-    return subprocess.check_output(command, universal_newlines=True)
+    return subprocess.check_output(command, text=True)
 
 
 def get_git_branch() -> str:
diff --git a/tools/test-queue-worker-reload b/tools/test-queue-worker-reload
index 479f8bef82..4ee137cd6e 100755
--- a/tools/test-queue-worker-reload
+++ b/tools/test-queue-worker-reload
@@ -66,7 +66,7 @@ if __name__ == "__main__":
         bufsize=1,  # line buffered
         stdout=subprocess.PIPE,
         stderr=subprocess.STDOUT,
-        universal_newlines=True,
+        text=True,
     )
     failed = check_worker_launch(run_dev)
 
diff --git a/tools/update-zuliprc-api-field b/tools/update-zuliprc-api-field
index 290cd6e606..c9fde4f53d 100755
--- a/tools/update-zuliprc-api-field
+++ b/tools/update-zuliprc-api-field
@@ -62,9 +62,7 @@ for zuliprc_path in zuliprc_paths_list:
             arguments = ["./manage.py", "print_initial_password", email]
         # We redirect 'stderr' to 'stdout' to avoid 'Connection to 127.0.0.1 closed'
         # appearing after this script finishes.
-        output = subprocess.check_output(
-            arguments, stderr=subprocess.STDOUT, universal_newlines=True
-        )
+        output = subprocess.check_output(arguments, stderr=subprocess.STDOUT, text=True)
         new_key = output.split()[6]
 
         if new_key != key:
diff --git a/zerver/lib/mdiff.py b/zerver/lib/mdiff.py
index bca684a823..ccd58c521b 100755
--- a/zerver/lib/mdiff.py
+++ b/zerver/lib/mdiff.py
@@ -16,5 +16,5 @@ def diff_strings(output: str, expected_output: str) -> str:
         raise DiffException(msg)
 
     command = ["node", mdiff_path, output, expected_output]
-    diff = subprocess.check_output(command, universal_newlines=True)
+    diff = subprocess.check_output(command, text=True)
     return diff
diff --git a/zerver/lib/test_fixtures.py b/zerver/lib/test_fixtures.py
index 3db3a1d2a0..7fa9a59395 100644
--- a/zerver/lib/test_fixtures.py
+++ b/zerver/lib/test_fixtures.py
@@ -370,7 +370,7 @@ def destroy_leaked_test_databases(expiry_time: int = 60 * 60) -> int:
         ["psql", "-q", "-v", "ON_ERROR_STOP=1", "-h", "localhost", "postgres", "zulip_test"],
         input=commands,
         check=True,
-        universal_newlines=True,
+        text=True,
     )
     return len(databases_to_drop)
 
diff --git a/zerver/lib/tex.py b/zerver/lib/tex.py
index 441df8313c..d3bfd37c0b 100644
--- a/zerver/lib/tex.py
+++ b/zerver/lib/tex.py
@@ -34,9 +34,7 @@ def render_tex(tex: str, is_inline: bool = True) -> Optional[str]:
     if not is_inline:
         command.extend(["--display-mode"])
     try:
-        stdout = subprocess.check_output(
-            command, input=tex, stderr=subprocess.DEVNULL, universal_newlines=True
-        )
+        stdout = subprocess.check_output(command, input=tex, stderr=subprocess.DEVNULL, text=True)
         # stdout contains a newline at the end
         return stdout.strip()
     except subprocess.CalledProcessError:
diff --git a/zerver/logging_handlers.py b/zerver/logging_handlers.py
index 5b5e3e8684..e38e8fe24d 100644
--- a/zerver/logging_handlers.py
+++ b/zerver/logging_handlers.py
@@ -25,7 +25,7 @@ def try_git_describe() -> Optional[str]:
             ["git", "describe", "--tags", "--match=[0-9]*", "--always", "--dirty", "--long"],
             stderr=subprocess.PIPE,
             cwd=os.path.join(os.path.dirname(__file__), ".."),
-            universal_newlines=True,
+            text=True,
         ).strip()
     except (FileNotFoundError, subprocess.CalledProcessError):  # nocoverage
         return None
diff --git a/zerver/management/commands/compilemessages.py b/zerver/management/commands/compilemessages.py
index 1b0d89ed6f..322575c925 100644
--- a/zerver/management/commands/compilemessages.py
+++ b/zerver/management/commands/compilemessages.py
@@ -70,7 +70,7 @@ class Command(compilemessages.Command):
             raise Exception(f"Unknown language {locale}")
 
     def get_locales(self) -> List[str]:
-        output = check_output(["git", "ls-files", "locale"], universal_newlines=True)
+        output = check_output(["git", "ls-files", "locale"], text=True)
         tracked_files = output.split()
         regex = re.compile(r"locale/(\w+)/LC_MESSAGES/django.po")
         locales = ["en"]
diff --git a/zerver/openapi/javascript_examples.py b/zerver/openapi/javascript_examples.py
index 56dc09cd28..5305163f65 100644
--- a/zerver/openapi/javascript_examples.py
+++ b/zerver/openapi/javascript_examples.py
@@ -20,7 +20,7 @@ def test_js_bindings(client: Client) -> None:
 
     output = subprocess.check_output(
         args=["node", "--unhandled-rejections=strict", "zerver/openapi/javascript_examples.js"],
-        universal_newlines=True,
+        text=True,
     )
     endpoint_responses = json.loads(output)
 
diff --git a/zerver/openapi/test_curl_examples.py b/zerver/openapi/test_curl_examples.py
index 65eba9bc28..8184bf67e2 100644
--- a/zerver/openapi/test_curl_examples.py
+++ b/zerver/openapi/test_curl_examples.py
@@ -98,9 +98,7 @@ def test_generated_curl_examples_for_success(client: Client) -> None:
                 try:
                     # We split this across two lines so if curl fails and
                     # returns non-JSON output, we'll still print it.
-                    response_json = subprocess.check_output(
-                        generated_curl_command, universal_newlines=True
-                    )
+                    response_json = subprocess.check_output(generated_curl_command, text=True)
                     response = json.loads(response_json)
                     assert response["result"] == "success"
                 except (AssertionError, Exception):
diff --git a/zerver/tests/test_email_mirror.py b/zerver/tests/test_email_mirror.py
index 8a53aad063..002c478a46 100644
--- a/zerver/tests/test_email_mirror.py
+++ b/zerver/tests/test_email_mirror.py
@@ -1283,7 +1283,7 @@ class TestScriptMTA(ZulipTestCase):
             [script, "-r", stream_to_address, "-s", settings.SHARED_SECRET, "-t"],
             input=mail,
             check=True,
-            universal_newlines=True,
+            text=True,
         )
 
     def test_error_no_recipient(self) -> None:
@@ -1298,7 +1298,7 @@ class TestScriptMTA(ZulipTestCase):
             [script, "-s", settings.SHARED_SECRET, "-t"],
             input=mail,
             stdout=subprocess.PIPE,
-            universal_newlines=True,
+            text=True,
         )
         self.assertEqual(
             p.stdout,
diff --git a/zerver/views/report.py b/zerver/views/report.py
index 29ae2ef4e3..d4d4a51fef 100644
--- a/zerver/views/report.py
+++ b/zerver/views/report.py
@@ -134,7 +134,7 @@ def report_error(
     try:
         version: Optional[str] = subprocess.check_output(
             ["git", "show", "-s", "--oneline"],
-            universal_newlines=True,
+            text=True,
         )
     except (FileNotFoundError, subprocess.CalledProcessError):
         version = None