diff --git a/pre_commit/commands/run.py b/pre_commit/commands/run.py
index 429e04c60..0831e6ed2 100644
--- a/pre_commit/commands/run.py
+++ b/pre_commit/commands/run.py
@@ -304,7 +304,7 @@ def _run_hooks(
         git_color_opt = 'always' if args.color else 'never'
         subprocess.call((
             'git', '--no-pager', 'diff', '--no-ext-diff',
-            f'--color={git_color_opt}',
+            '--ignore-submodules', f'--color={git_color_opt}',
         ))
 
     return retval
@@ -317,8 +317,8 @@ def _has_unmerged_paths() -> bool:
 
 def _has_unstaged_config(config_file: str) -> bool:
     retcode, _, _ = cmd_output_b(
-        'git', 'diff', '--no-ext-diff', '--exit-code', config_file,
-        check=False,
+        'git', 'diff', '--no-ext-diff', '--ignore-submodules',
+        '--exit-code', config_file, check=False,
     )
     # be explicit, other git errors don't mean it has an unstaged config.
     return retcode == 1
diff --git a/pre_commit/git.py b/pre_commit/git.py
index 99538b1b9..5eed0f5a4 100644
--- a/pre_commit/git.py
+++ b/pre_commit/git.py
@@ -130,8 +130,9 @@ def get_conflicted_files() -> set[str]:
     tree_hash = cmd_output('git', 'write-tree')[1].strip()
     merge_diff_filenames = zsplit(
         cmd_output(
-            'git', 'diff', '--name-only', '--no-ext-diff', '-z',
-            '-m', tree_hash, 'HEAD', 'MERGE_HEAD',
+            'git', 'diff', '--name-only', '--no-ext-diff',
+            '--ignore-submodules', '-z', '-m',
+            tree_hash, 'HEAD', 'MERGE_HEAD',
         )[1],
     )
     return set(merge_conflict_filenames) | set(merge_diff_filenames)
@@ -150,7 +151,8 @@ def get_staged_files(cwd: str | None = None) -> list[str]:
 
 def intent_to_add_files() -> list[str]:
     _, stdout, _ = cmd_output(
-        'git', 'diff', '--diff-filter=A', '--name-only', '-z',
+        'git', 'diff', '--no-ext-diff', '--ignore-submodules',
+        '--diff-filter=A', '--name-only', '-z',
     )
     return zsplit(stdout)
 
@@ -160,7 +162,10 @@ def get_all_files() -> list[str]:
 
 
 def get_changed_files(old: str, new: str) -> list[str]:
-    diff_cmd = ('git', 'diff', '--name-only', '--no-ext-diff', '-z')
+    diff_cmd = (
+        'git', 'diff', '--name-only', '--no-ext-diff',
+        '--ignore-submodules', '-z',
+    )
     try:
         _, out, _ = cmd_output(*diff_cmd, f'{old}...{new}')
     except CalledProcessError:  # pragma: no cover (new git)
@@ -177,7 +182,10 @@ def head_rev(remote: str) -> str:
 
 
 def has_diff(*args: str, repo: str = '.') -> bool:
-    cmd = ('git', 'diff', '--quiet', '--no-ext-diff', *args)
+    cmd = (
+        'git', 'diff', '--quiet', '--no-ext-diff',
+        '--ignore-submodules', *args,
+    )
     return cmd_output_b(*cmd, cwd=repo, check=False)[0] == 1