diff --git a/ios/chrome/browser/ui/settings/privacy/BUILD.gn b/ios/chrome/browser/ui/settings/privacy/BUILD.gn
index 771c821c62524c..e756f1e313e293 100644
--- a/ios/chrome/browser/ui/settings/privacy/BUILD.gn
+++ b/ios/chrome/browser/ui/settings/privacy/BUILD.gn
@@ -146,6 +146,7 @@ source_set("unit_tests") {
     "//ios/chrome/browser/ui/table_view:utils",
     "//ios/chrome/browser/ui/table_view/cells",
     "//ios/chrome/test:test_support",
+    "//ios/components/security_interstitials/https_only_mode:feature",
     "//ios/web/public/test",
     "//testing/gtest",
     "//third_party/ocmock:ocmock",
diff --git a/ios/chrome/browser/ui/settings/privacy/privacy_table_view_controller_unittest.mm b/ios/chrome/browser/ui/settings/privacy/privacy_table_view_controller_unittest.mm
index f7cb5c52eb6485..349c906da063f6 100644
--- a/ios/chrome/browser/ui/settings/privacy/privacy_table_view_controller_unittest.mm
+++ b/ios/chrome/browser/ui/settings/privacy/privacy_table_view_controller_unittest.mm
@@ -32,6 +32,7 @@
 #include "ios/chrome/grit/ios_chromium_strings.h"
 #include "ios/chrome/grit/ios_strings.h"
 #include "ios/chrome/test/ios_chrome_scoped_testing_local_state.h"
+#import "ios/components/security_interstitials/https_only_mode/feature.h"
 #include "ios/web/public/test/web_task_environment.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -63,6 +64,8 @@ typedef NS_ENUM(NSUInteger, PrivacyTableViewControllerTestConfig) {
   PrivacyTableViewControllerTestConfigEnhancedProtectionEnabled = 1 << 0,
   // Tests should run with Third-party intents in Incognito flag enabled.
   PrivacyTableViewControllerTestConfig3PIntentsInIncognitoEnabled = 1 << 1,
+  // Tests should run with HTTPS-Only Mode flag enabled.
+  PrivacyTableViewControllerTestConfigHttpsOnlyModeSettingEnabled = 1 << 2,
 };
 
 // `ScopedFeatureList` wrapper so `PrivacyTableViewControllerTest` can ensure
@@ -110,6 +113,15 @@ typedef NS_ENUM(NSUInteger, PrivacyTableViewControllerTestConfig) {
       enabledDisabledFeatures.second.push_back(kIOS3PIntentsInIncognito);
     }
 
+    if (GetParam() &
+        PrivacyTableViewControllerTestConfigHttpsOnlyModeSettingEnabled) {
+      enabledDisabledFeatures.first.push_back(
+          security_interstitials::features::kHttpsOnlyMode);
+    } else {
+      enabledDisabledFeatures.second.push_back(
+          security_interstitials::features::kHttpsOnlyMode);
+    }
+
     return enabledDisabledFeatures;
   }
 
diff --git a/ios/components/security_interstitials/https_only_mode/feature.cc b/ios/components/security_interstitials/https_only_mode/feature.cc
index 79f261d6adb42a..93b03fdb66512f 100644
--- a/ios/components/security_interstitials/https_only_mode/feature.cc
+++ b/ios/components/security_interstitials/https_only_mode/feature.cc
@@ -8,7 +8,7 @@ namespace security_interstitials {
 namespace features {
 
 const base::Feature kHttpsOnlyMode{"HttpsOnlyMode",
-                                   base::FEATURE_DISABLED_BY_DEFAULT};
+                                   base::FEATURE_ENABLED_BY_DEFAULT};
 
 }  // namespace features
 }  // namespace security_interstitials
diff --git a/ios/components/security_interstitials/https_only_mode/feature.h b/ios/components/security_interstitials/https_only_mode/feature.h
index 8ba9d64c352806..2d17ddff14a38a 100644
--- a/ios/components/security_interstitials/https_only_mode/feature.h
+++ b/ios/components/security_interstitials/https_only_mode/feature.h
@@ -10,7 +10,8 @@
 namespace security_interstitials {
 namespace features {
 
-// Enables HTTPS-Only mode upgrades on iOS.
+// Enables the HTTPS-Only mode UI setting on iOS. The user has to enable
+// the UI setting under "Privacy and Security" to use HTTPS-Only Mode.
 extern const base::Feature kHttpsOnlyMode;
 
 }  // namespace features