diff --git a/git_cl.py b/git_cl.py
index 74ece83abb..954ab206b0 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -2055,15 +2055,6 @@ class Changelist(object):
         if not options.private and not options.no_autocc and not self.GetIssue(
         ):
             ccs = self.GetCCList().split(',')
-            if len(ccs) > 100:
-                lsc = (
-                    'https://chromium.googlesource.com/chromium/src/+/HEAD/docs/'
-                    'process/lsc/lsc_workflow.md')
-                print('WARNING: This will auto-CC %s users.' % len(ccs))
-                print('LSC may be more appropriate: %s' % lsc)
-                print(
-                    'You can also use the --no-autocc flag to disable auto-CC.')
-                confirm_or_exit(action='continue')
 
         # Add ccs from the --cc flag.
         if options.cc:
@@ -3120,13 +3111,6 @@ class Changelist(object):
         if not options.private and not options.no_autocc and not self.GetIssue(
         ):
             cc = self.GetCCList().split(',')
-        if len(cc) > 100:
-            lsc = ('https://chromium.googlesource.com/chromium/src/+/HEAD/docs/'
-                   'process/lsc/lsc_workflow.md')
-            print('WARNING: This will auto-CC %s users.' % len(cc))
-            print('LSC may be more appropriate: %s' % lsc)
-            print('You can also use the --no-autocc flag to disable auto-CC.')
-            confirm_or_exit(action='continue')
         # Add cc's from the --cc flag.
         if options.cc:
             cc.extend(options.cc)
diff --git a/presubmit_canned_checks.py b/presubmit_canned_checks.py
index 57cbace25a..8c2cc28270 100644
--- a/presubmit_canned_checks.py
+++ b/presubmit_canned_checks.py
@@ -270,6 +270,20 @@ def CheckCorpLinksInFiles(input_api, output_api, source_file_filter=None):
     return []
 
 
+def CheckLargeScaleChange(input_api, output_api):
+    """Checks if the change should go through the LSC process."""
+    size = len(input_api.AffectedFiles())
+    if size <= 100:
+        return []
+    return [
+        output_api.PresubmitPromptWarning(
+            f'This change contains {size} files.\n'
+            'Consider using the LSC (large scale change) process.\n'
+            'See https://chromium.googlesource.com/chromium/src/+/HEAD/docs/process/lsc/lsc_workflow.md.'  # pylint: disable=line-too-long
+        )
+    ]
+
+
 def GetCppLintFilters(lint_filters=None):
     filters = OFF_UNLESS_MANUALLY_ENABLED_LINT_FILTERS[:]
     if lint_filters is None:
@@ -1709,6 +1723,9 @@ def PanProjectChecks(input_api,
     results.extend(
         input_api.canned_checks.CheckCorpLinksInFiles(
             input_api, output_api, source_file_filter=sources))
+    snapshot("checking large scale change")
+    results.extend(
+        input_api.canned_checks.CheckLargeScaleChange(input_api, output_api))
 
     if input_api.is_committing:
         if global_checks:
diff --git a/tests/presubmit_unittest.py b/tests/presubmit_unittest.py
index a510df36b1..de9026b710 100755
--- a/tests/presubmit_unittest.py
+++ b/tests/presubmit_unittest.py
@@ -2035,6 +2035,33 @@ class CannedChecksUnittest(PresubmitTestsBase):
                          'chromium.git.corp.google.com', None,
                          presubmit.OutputApi.PresubmitPromptWarning)
 
+    def testCannedCheckLargeScaleChange(self):
+        input_api = self.MockInputApi(
+            presubmit.Change('foo', 'foo1', self.fake_root_dir, None, 0, 0,
+                             None), False)
+        affected_files = []
+        for i in range(100):
+            affected_file = mock.MagicMock(presubmit.GitAffectedFile)
+            affected_file.LocalPath.return_value = f'foo{i}.cc'
+            affected_files.append(affected_file)
+        input_api.AffectedFiles = lambda **_: affected_files
+
+        # Don't warn if less than or equal to 100 files.
+        results = presubmit_canned_checks.CheckLargeScaleChange(
+            input_api, presubmit.OutputApi)
+        self.assertEqual(len(results), 0)
+
+        # Warn if greater than 100 files.
+        affected_files.append('bar.cc')
+
+        results = presubmit_canned_checks.CheckLargeScaleChange(
+            input_api, presubmit.OutputApi)
+        self.assertEqual(len(results), 1)
+        result = results[0]
+        self.assertEqual(result.__class__,
+                         presubmit.OutputApi.PresubmitPromptWarning)
+        self.assertIn("large scale change", result.json_format()['message'])
+
     def testCheckChangeHasNoStrayWhitespace(self):
         self.ContentTest(
             lambda x, y, z: presubmit_canned_checks.