diff --git a/ios/chrome/app/BUILD.gn b/ios/chrome/app/BUILD.gn
index 9a37d1f4ecb223..8876046a2e431a 100644
--- a/ios/chrome/app/BUILD.gn
+++ b/ios/chrome/app/BUILD.gn
@@ -64,6 +64,7 @@ source_set("unit_tests") {
     "//ios/chrome/browser/prefs:browser_prefs",
     "//ios/chrome/browser/tabs",
     "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/main/test",
     "//ios/chrome/browser/ui/safe_mode",
     "//ios/chrome/common/app_group",
@@ -169,7 +170,7 @@ source_set("app_metrics_app_state_agent") {
     "//ios/chrome/app/application_delegate:application_delegate_internal",
     "//ios/chrome/app/application_delegate:observing_app_state_agent",
     "//ios/chrome/browser/metrics",
-    "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
   ]
 }
 
@@ -248,7 +249,7 @@ source_set("first_run_app_state_agent") {
     "//ios/chrome/browser/ui/first_run:utils",
     "//ios/chrome/browser/ui/main:browser_interface_provider",
     "//ios/chrome/browser/ui/main:observing_scene_agent",
-    "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/screen:screen_provider",
   ]
 }
@@ -358,6 +359,7 @@ source_set("app_internal") {
     "//ios/chrome/browser/ui/first_run:utils",
     "//ios/chrome/browser/ui/main",
     "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/tab_switcher/tab_grid",
     "//ios/chrome/browser/ui/tab_switcher/tab_grid:tab_grid_ui",
     "//ios/chrome/browser/ui/table_view",
diff --git a/ios/chrome/app/application_delegate/BUILD.gn b/ios/chrome/app/application_delegate/BUILD.gn
index 8c8412d75ce33a..33b5fed844a41b 100644
--- a/ios/chrome/app/application_delegate/BUILD.gn
+++ b/ios/chrome/app/application_delegate/BUILD.gn
@@ -171,6 +171,7 @@ source_set("observing_app_state_agent") {
   public_deps = [
     ":app_state_header",
     "//ios/chrome/browser/ui/main:scene_state_header",
+    "//ios/chrome/browser/ui/main:scene_state_observer",
   ]
 }
 
diff --git a/ios/chrome/browser/ntp/new_tab_page_tab_helper.h b/ios/chrome/browser/ntp/new_tab_page_tab_helper.h
index 06e8c992fa74cd..4e55697a196d61 100644
--- a/ios/chrome/browser/ntp/new_tab_page_tab_helper.h
+++ b/ios/chrome/browser/ntp/new_tab_page_tab_helper.h
@@ -33,6 +33,10 @@ class NewTabPageTabHelper : public web::WebStateObserver,
   // Sets the delegate. The delegate is not owned by the tab helper.
   void SetDelegate(id<NewTabPageTabHelperDelegate> delegate);
 
+  // Setter/Getter for whether to show the Start Surface.
+  bool ShouldShowStartSurface() const;
+  void SetShowStartSurface(bool show_start_surface);
+
   // Returns true when the current web_state is an NTP and the underlying
   // controllers have been created.
   bool IsActive() const;
@@ -106,6 +110,10 @@ class NewTabPageTabHelper : public web::WebStateObserver,
   // |YES| if the current tab helper is active.
   BOOL active_ = NO;
 
+  // |YES| if the NTP for this WebState should be configured to show the Start
+  // Surface.
+  BOOL show_start_surface_ = false;
+
   // |YES| if the NTP's underlying ios/web page is still loading.
   BOOL ignore_load_requests_ = NO;
 
diff --git a/ios/chrome/browser/ntp/new_tab_page_tab_helper.mm b/ios/chrome/browser/ntp/new_tab_page_tab_helper.mm
index b6b4e39fdf6f0f..b622952c17f4cd 100644
--- a/ios/chrome/browser/ntp/new_tab_page_tab_helper.mm
+++ b/ios/chrome/browser/ntp/new_tab_page_tab_helper.mm
@@ -70,6 +70,14 @@
   }
 }
 
+bool NewTabPageTabHelper::ShouldShowStartSurface() const {
+  return show_start_surface_;
+}
+
+void NewTabPageTabHelper::SetShowStartSurface(bool show_start_surface) {
+  show_start_surface_ = show_start_surface;
+}
+
 bool NewTabPageTabHelper::IsActive() const {
   return active_;
 }
diff --git a/ios/chrome/browser/ui/authentication/BUILD.gn b/ios/chrome/browser/ui/authentication/BUILD.gn
index b64d53e85a773c..be162a5955e4be 100644
--- a/ios/chrome/browser/ui/authentication/BUILD.gn
+++ b/ios/chrome/browser/ui/authentication/BUILD.gn
@@ -189,7 +189,7 @@ source_set("eg_app_support+eg2") {
     "//ios/chrome/browser/ui/authentication/unified_consent:unified_consent_ui",
     "//ios/chrome/browser/ui/authentication/unified_consent/identity_chooser:identity_chooser_ui",
     "//ios/chrome/browser/ui/commands",
-    "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/util",
     "//ios/chrome/test/app:test_support",
     "//ios/public/provider/chrome/browser/signin:fake_chrome_identity",
diff --git a/ios/chrome/browser/ui/browser_view/BUILD.gn b/ios/chrome/browser/ui/browser_view/BUILD.gn
index e343323ff45979..982251656f27a7 100644
--- a/ios/chrome/browser/ui/browser_view/BUILD.gn
+++ b/ios/chrome/browser/ui/browser_view/BUILD.gn
@@ -154,6 +154,7 @@ source_set("browser_view") {
     "//ios/chrome/browser/ui/sharing",
     "//ios/chrome/browser/ui/side_swipe",
     "//ios/chrome/browser/ui/snackbar",
+    "//ios/chrome/browser/ui/start_surface:feature_flags",
     "//ios/chrome/browser/ui/tab_switcher/tab_strip",
     "//ios/chrome/browser/ui/tabs",
     "//ios/chrome/browser/ui/tabs:constants",
diff --git a/ios/chrome/browser/ui/browser_view/browser_view_controller.mm b/ios/chrome/browser/ui/browser_view/browser_view_controller.mm
index 61aad823044e19..74c4a086d2f78d 100644
--- a/ios/chrome/browser/ui/browser_view/browser_view_controller.mm
+++ b/ios/chrome/browser/ui/browser_view/browser_view_controller.mm
@@ -102,6 +102,7 @@
 #import "ios/chrome/browser/ui/settings/sync/utils/sync_util.h"
 #import "ios/chrome/browser/ui/side_swipe/side_swipe_controller.h"
 #import "ios/chrome/browser/ui/side_swipe/swipe_view.h"
+#import "ios/chrome/browser/ui/start_surface/start_surface_features.h"
 #import "ios/chrome/browser/ui/tab_switcher/tab_strip/tab_strip_coordinator.h"
 #import "ios/chrome/browser/ui/tabs/background_tab_animation_view.h"
 #import "ios/chrome/browser/ui/tabs/foreground_tab_animation_view.h"
@@ -4034,8 +4035,14 @@ - (void)webStateList:(WebStateList*)webStateList
                       self /* id<SyncPresenter> */);
   }
 
+  BOOL inBackground = !activating;
+  if (IsStartSurfaceSplashStartupEnabled()) {
+    inBackground =
+        inBackground ||
+        NewTabPageTabHelper::FromWebState(webState)->ShouldShowStartSurface();
+  }
   [self initiateNewTabAnimationForWebState:webState
-                      willOpenInBackground:!activating];
+                      willOpenInBackground:inBackground];
 }
 
 #pragma mark - WebStateListObserver helpers (new tab animations)
@@ -4372,7 +4379,8 @@ - (void)captivePortalTabHelper:(CaptivePortalTabHelper*)tabHelper
       web_navigation_util::CreateWebLoadParams(
           landingURL, ui::PAGE_TRANSITION_TYPED, nullptr),
       nil, false, self.browser->GetWebStateList()->count(),
-      /*in_background=*/false, /*inherit_opener=*/false);
+      /*in_background=*/false, /*inherit_opener=*/false,
+      /*should_show_start_surface=*/false);
 }
 
 #pragma mark - PageInfoPresentation
diff --git a/ios/chrome/browser/ui/content_suggestions/content_suggestions_coordinator.mm b/ios/chrome/browser/ui/content_suggestions/content_suggestions_coordinator.mm
index 1bdfc4e8223b38..7395446f184b45 100644
--- a/ios/chrome/browser/ui/content_suggestions/content_suggestions_coordinator.mm
+++ b/ios/chrome/browser/ui/content_suggestions/content_suggestions_coordinator.mm
@@ -24,6 +24,7 @@
 #include "ios/chrome/browser/favicon/ios_chrome_large_icon_service_factory.h"
 #include "ios/chrome/browser/favicon/large_icon_cache.h"
 #import "ios/chrome/browser/main/browser.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
 #include "ios/chrome/browser/ntp_tiles/ios_most_visited_sites_factory.h"
 #import "ios/chrome/browser/policy/policy_util.h"
 #include "ios/chrome/browser/pref_names.h"
@@ -340,7 +341,6 @@ - (void)viewDidDisappear {
   DiscoverFeedServiceFactory::GetForBrowserState(
       self.browser->GetBrowserState())
       ->SetIsShownOnStartSurface(false);
-  // Update DiscoverFeedService to NO
   if (ShouldShowReturnToMostRecentTabForStartSurface()) {
     [self.contentSuggestionsMediator hideRecentTabTile];
   }
@@ -510,8 +510,14 @@ - (UIContextMenuConfiguration*)contextMenuConfigurationForItem:
 - (void)configureStartSurfaceIfNeeded {
   SceneState* scene =
       SceneStateBrowserAgent::FromBrowser(self.browser)->GetSceneState();
-  if (!scene.modifytVisibleNTPForStartSurface)
+  if (IsStartSurfaceSplashStartupEnabled()) {
+    if (!NewTabPageTabHelper::FromWebState(self.webState)
+             ->ShouldShowStartSurface()) {
+      return;
+    }
+  } else if (!scene.modifytVisibleNTPForStartSurface) {
     return;
+  }
 
   // Update Mediator property to signal the NTP is currently showing Start.
   self.contentSuggestionsMediator.showingStartSurface = YES;
@@ -544,7 +550,12 @@ - (void)configureStartSurfaceIfNeeded {
     base::RecordAction(
         base::UserMetricsAction("IOS.StartSurface.HideShortcuts"));
   }
-  scene.modifytVisibleNTPForStartSurface = NO;
+  if (IsStartSurfaceSplashStartupEnabled()) {
+    NewTabPageTabHelper::FromWebState(self.webState)
+        ->SetShowStartSurface(false);
+  } else {
+    scene.modifytVisibleNTPForStartSurface = NO;
+  }
 }
 
 // Triggers the URL sharing flow for the given |URL| and |title|, with the
diff --git a/ios/chrome/browser/ui/first_run/BUILD.gn b/ios/chrome/browser/ui/first_run/BUILD.gn
index 13b8cceb01dbc6..148ba62e7f3b8a 100644
--- a/ios/chrome/browser/ui/first_run/BUILD.gn
+++ b/ios/chrome/browser/ui/first_run/BUILD.gn
@@ -270,7 +270,7 @@ source_set("eg_app_support+eg2") {
     "//ios/chrome/browser",
     "//ios/chrome/browser/sync",
     "//ios/chrome/browser/ui:feature_flags",
-    "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/main:scene_testing",
     "//ios/chrome/test/app:test_support",
     "//ios/third_party/earl_grey2:app_framework+link",
diff --git a/ios/chrome/browser/ui/main/BUILD.gn b/ios/chrome/browser/ui/main/BUILD.gn
index e6ff1761160c92..31292d17563f7e 100644
--- a/ios/chrome/browser/ui/main/BUILD.gn
+++ b/ios/chrome/browser/ui/main/BUILD.gn
@@ -36,13 +36,18 @@ source_set("observing_scene_agent") {
 source_set("scene_state_header") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
+    "connection_information.h",
+    "scene_controller.h",
     "scene_state.h",
     "scene_state_browser_agent.h",
   ]
   public_deps = [
     ":scene_state_observer",
+    "//ios/chrome/app/application_delegate:tab_opening",
     "//ios/chrome/browser/main:public",
+    "//ios/chrome/browser/ui/commands",
     "//ios/chrome/browser/ui/scoped_ui_blocker",
+    "//ios/chrome/browser/web_state_list",
     "//ios/chrome/browser/window_activities",
   ]
 }
@@ -82,8 +87,6 @@ source_set("incognito_blocker_scene_agent") {
 source_set("scene") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
-    "connection_information.h",
-    "scene_controller.h",
     "scene_controller.mm",
     "scene_delegate.h",
     "scene_delegate.mm",
@@ -99,6 +102,7 @@ source_set("scene") {
     ":incognito_blocker_scene_agent",
     ":main",
     ":observing_scene_agent",
+    ":scene_state_header",
     ":scene_testing",
     "//base",
     "//base/ios",
@@ -164,6 +168,7 @@ source_set("scene") {
     "//ios/chrome/browser/ui/settings:settings_root",
     "//ios/chrome/browser/ui/settings/sync",
     "//ios/chrome/browser/ui/start_surface",
+    "//ios/chrome/browser/ui/start_surface:feature_flags",
     "//ios/chrome/browser/ui/tab_switcher/tab_grid",
     "//ios/chrome/browser/ui/thumb_strip:feature_flags",
     "//ios/chrome/browser/ui/toolbar/public",
diff --git a/ios/chrome/browser/ui/main/scene_controller.h b/ios/chrome/browser/ui/main/scene_controller.h
index 583c145e316772..5251e0a638a00b 100644
--- a/ios/chrome/browser/ui/main/scene_controller.h
+++ b/ios/chrome/browser/ui/main/scene_controller.h
@@ -39,6 +39,9 @@
 // YES if the scene is presenting the signin view.
 @property(nonatomic, readonly) BOOL isPresentingSigninView;
 
+// YES if the tab grid is the main user interface at the moment.
+@property(nonatomic, readonly, getter=isTabGridVisible) BOOL tabGridVisible;
+
 // The view controller that is active. Can be either a BrowserViewController or
 // TabGridViewController.
 @property(nonatomic, readonly) UIViewController* activeViewController;
diff --git a/ios/chrome/browser/ui/main/scene_controller.mm b/ios/chrome/browser/ui/main/scene_controller.mm
index e9eac0d5c4a394..47b34987c39b15 100644
--- a/ios/chrome/browser/ui/main/scene_controller.mm
+++ b/ios/chrome/browser/ui/main/scene_controller.mm
@@ -102,6 +102,7 @@
 #import "ios/chrome/browser/ui/main/ui_blocker_scene_agent.h"
 #import "ios/chrome/browser/ui/scoped_ui_blocker/scoped_ui_blocker.h"
 #import "ios/chrome/browser/ui/settings/settings_navigation_controller.h"
+#import "ios/chrome/browser/ui/start_surface/start_surface_features.h"
 #import "ios/chrome/browser/ui/start_surface/start_surface_recent_tab_browser_agent.h"
 #import "ios/chrome/browser/ui/start_surface/start_surface_scene_agent.h"
 #import "ios/chrome/browser/ui/start_surface/start_surface_util.h"
@@ -361,6 +362,10 @@ - (BOOL)isPresentingSigninView {
   return self.signinCoordinator != nil;
 }
 
+- (BOOL)tabGridVisible {
+  return self.mainCoordinator.isTabGridActive;
+}
+
 - (UIViewController*)activeViewController {
   return self.mainCoordinator.activeViewController;
 }
@@ -711,7 +716,9 @@ - (void)transitionToSceneActivationLevel:(SceneActivationLevel)level
       [self finishActivatingBrowserDismissingTabSwitcher:YES];
     }
 
-    [self handleShowStartSurfaceIfNecessary];
+    if (!IsStartSurfaceSplashStartupEnabled()) {
+      [self handleShowStartSurfaceIfNecessary];
+    }
   }
 
   [self recordWindowCreationForSceneState:self.sceneState];
@@ -977,7 +984,9 @@ - (void)createInitialUI:(ApplicationMode)launchMode {
   // currentInterface is set in case a new tab needs to be opened. Since this is
   // synchronous with |setActivePage:| above, then the user should not see the
   // last tab if the Start Surface is opened.
-  [self handleShowStartSurfaceIfNecessary];
+  if (!IsStartSurfaceSplashStartupEnabled()) {
+    [self handleShowStartSurfaceIfNecessary];
+  }
 
   // Figure out what UI to show initially.
 
@@ -3039,7 +3048,8 @@ - (void)addANewTabAndPresentBrowser:(Browser*)browser
                   withURLLoadParams:(const UrlLoadParams&)urlLoadParams {
   TabInsertionBrowserAgent::FromBrowser(browser)->InsertWebState(
       urlLoadParams.web_params, nil, false, browser->GetWebStateList()->count(),
-      /*in_background=*/false, /*inherit_opener=*/false);
+      /*in_background=*/false, /*inherit_opener=*/false,
+      /*should_show_start_surface=*/false);
   [self beginActivatingBrowser:browser dismissTabSwitcher:YES focusOmnibox:NO];
 }
 
diff --git a/ios/chrome/browser/ui/ntp/BUILD.gn b/ios/chrome/browser/ui/ntp/BUILD.gn
index a17fc3d0c20152..9a26a06a22f932 100644
--- a/ios/chrome/browser/ui/ntp/BUILD.gn
+++ b/ios/chrome/browser/ui/ntp/BUILD.gn
@@ -255,6 +255,7 @@ source_set("unit_tests") {
     "//ios/chrome/browser/browser_state:test_support",
     "//ios/chrome/browser/favicon",
     "//ios/chrome/browser/main:test_support",
+    "//ios/chrome/browser/ntp",
     "//ios/chrome/browser/ntp_snippets:ntp_snippets",
     "//ios/chrome/browser/search_engines",
     "//ios/chrome/browser/sessions",
diff --git a/ios/chrome/browser/ui/ntp/new_tab_page_coordinator_unittest.mm b/ios/chrome/browser/ui/ntp/new_tab_page_coordinator_unittest.mm
index 5ef99adc2cec67..2cca29dd13a39d 100644
--- a/ios/chrome/browser/ui/ntp/new_tab_page_coordinator_unittest.mm
+++ b/ios/chrome/browser/ui/ntp/new_tab_page_coordinator_unittest.mm
@@ -9,6 +9,7 @@
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state_manager.h"
 #include "ios/chrome/browser/favicon/ios_chrome_large_icon_service_factory.h"
 #include "ios/chrome/browser/main/test_browser.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
 #include "ios/chrome/browser/ntp_snippets/ios_chrome_content_suggestions_service_factory.h"
 #include "ios/chrome/browser/search_engines/template_url_service_factory.h"
 #import "ios/chrome/browser/signin/authentication_service_factory.h"
@@ -72,6 +73,7 @@ void CreateCoordinator(bool off_the_record) {
       scene_state_ = OCMClassMock([SceneState class]);
       SceneStateBrowserAgent::CreateForBrowser(browser_.get(), scene_state_);
     }
+    NewTabPageTabHelper::CreateForWebState(&web_state_);
     coordinator_ = [[NewTabPageCoordinator alloc]
         initWithBaseViewController:base_view_controller_
                            browser:browser_.get()];
diff --git a/ios/chrome/browser/ui/start_surface/BUILD.gn b/ios/chrome/browser/ui/start_surface/BUILD.gn
index 36b4a2b27d10de..12e6612fc34839 100644
--- a/ios/chrome/browser/ui/start_surface/BUILD.gn
+++ b/ios/chrome/browser/ui/start_surface/BUILD.gn
@@ -37,11 +37,13 @@ source_set("start_surface") {
     "//ios/chrome/app/application_delegate:app_state_header",
     "//ios/chrome/app/strings:ios_strings",
     "//ios/chrome/browser",
+    "//ios/chrome/browser/ntp",
     "//ios/chrome/browser/ui:feature_flags",
     "//ios/chrome/browser/ui/main:browser_interface_provider",
     "//ios/chrome/browser/ui/main:observing_scene_agent",
     "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/web_state_list",
+    "//ios/chrome/browser/web_state_list:agents",
     "//ios/web/public",
     "//ios/web/public:web_state_observer",
     "//ui/base",
diff --git a/ios/chrome/browser/ui/start_surface/start_surface_features.h b/ios/chrome/browser/ui/start_surface/start_surface_features.h
index 4889cdee4e18a1..6ab4e7c37698fd 100644
--- a/ios/chrome/browser/ui/start_surface/start_surface_features.h
+++ b/ios/chrome/browser/ui/start_surface/start_surface_features.h
@@ -15,6 +15,9 @@ extern const char kStartSurfaceReturnToRecentTabParam[];
 // The feature to enable or disable the Start Surface.
 extern const base::Feature kStartSurface;
 
+// The feature to use the new logic to open a new tab to show the Start Surface.
+extern const base::Feature kStartSurfaceSplashStartup;
+
 // The feature parameter to indicate inactive duration to return to the Start
 // Surface in seconds.
 extern const char kReturnToStartSurfaceInactiveDurationInSeconds[];
@@ -22,6 +25,9 @@ extern const char kReturnToStartSurfaceInactiveDurationInSeconds[];
 // Checks whether the Start Surface should be enabled.
 bool IsStartSurfaceEnabled();
 
+// Checks whether the Start Splash Startup change should be enabled.
+bool IsStartSurfaceSplashStartupEnabled();
+
 // Returns the inactive duration to show the Start Surface.
 double GetReturnToStartSurfaceDuration();
 
diff --git a/ios/chrome/browser/ui/start_surface/start_surface_features.mm b/ios/chrome/browser/ui/start_surface/start_surface_features.mm
index bb3c3625eac531..3aedc82d26173e 100644
--- a/ios/chrome/browser/ui/start_surface/start_surface_features.mm
+++ b/ios/chrome/browser/ui/start_surface/start_surface_features.mm
@@ -12,6 +12,9 @@
 const base::Feature kStartSurface{"StartSurface",
                                   base::FEATURE_ENABLED_BY_DEFAULT};
 
+const base::Feature kStartSurfaceSplashStartup{
+    "StartSurfaceSplashStartup", base::FEATURE_ENABLED_BY_DEFAULT};
+
 const char kReturnToStartSurfaceInactiveDurationInSeconds[] =
     "ReturnToStartSurfaceInactiveDurationInSeconds";
 
@@ -23,6 +26,10 @@ bool IsStartSurfaceEnabled() {
   return base::FeatureList::IsEnabled(kStartSurface);
 }
 
+bool IsStartSurfaceSplashStartupEnabled() {
+  return base::FeatureList::IsEnabled(kStartSurfaceSplashStartup);
+}
+
 double GetReturnToStartSurfaceDuration() {
   return base::GetFieldTrialParamByFeatureAsDouble(
       kStartSurface, kReturnToStartSurfaceInactiveDurationInSeconds,
diff --git a/ios/chrome/browser/ui/start_surface/start_surface_scene_agent.mm b/ios/chrome/browser/ui/start_surface/start_surface_scene_agent.mm
index c1428eb38113de..e040c155d3bcf6 100644
--- a/ios/chrome/browser/ui/start_surface/start_surface_scene_agent.mm
+++ b/ios/chrome/browser/ui/start_surface/start_surface_scene_agent.mm
@@ -5,14 +5,23 @@
 #import "ios/chrome/browser/ui/start_surface/start_surface_scene_agent.h"
 #include "base/feature_list.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/user_metrics.h"
+#include "base/metrics/user_metrics_action.h"
+#include "ios/chrome/browser/chrome_url_constants.h"
 #import "ios/chrome/browser/chrome_url_util.h"
 #import "ios/chrome/browser/main/browser.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
 #import "ios/chrome/browser/ui/main/browser_interface_provider.h"
+#import "ios/chrome/browser/ui/main/scene_controller.h"
+#import "ios/chrome/browser/ui/start_surface/start_surface_features.h"
+#import "ios/chrome/browser/ui/start_surface/start_surface_recent_tab_browser_agent.h"
 #import "ios/chrome/browser/ui/start_surface/start_surface_util.h"
 #include "ios/chrome/browser/ui/ui_feature_flags.h"
+#import "ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h"
 #import "ios/chrome/browser/web_state_list/web_state_list.h"
 #import "ios/web/public/navigation/navigation_manager.h"
 #import "ios/web/public/web_state.h"
+#include "url/gurl.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -61,9 +70,64 @@ - (void)sceneState:(SceneState*)sceneState
                                           .incognitoInterface.browser];
     }
   }
+  if (level >= SceneActivationLevelForegroundInactive &&
+      self.previousActivationLevel < SceneActivationLevelForegroundInactive) {
+    if (IsStartSurfaceSplashStartupEnabled()) {
+      [self handleShowStartSurfaceIfNecessary];
+    }
+  }
   self.previousActivationLevel = level;
 }
 
+- (void)handleShowStartSurfaceIfNecessary {
+  if (!ShouldShowStartSurfaceForSceneState(self.sceneState)) {
+    return;
+  }
+
+  // Do not show the Start Surface no matter whether it is enabled or not when
+  // the Tab grid is active by design.
+  if (self.sceneState.controller.isTabGridVisible) {
+    return;
+  }
+
+  // If there is no active tab, a NTP will be added, and since there is no
+  // recent tab, there is no need to mark |modifytVisibleNTPForStartSurface|.
+  // Keep showing the last active NTP tab no matter whether the Start Surface is
+  // enabled or not by design.
+  // Note that activeWebState could only be nullptr when the Tab grid is active
+  // for now.
+  web::WebState* activeWebState =
+      self.sceneState.interfaceProvider.mainInterface.browser->GetWebStateList()
+          ->GetActiveWebState();
+  if (!activeWebState || IsURLNtp(activeWebState->GetVisibleURL())) {
+    return;
+  }
+
+  base::RecordAction(base::UserMetricsAction("IOS.StartSurface.Show"));
+  Browser* browser = self.sceneState.interfaceProvider.mainInterface.browser;
+  StartSurfaceRecentTabBrowserAgent::FromBrowser(browser)->SaveMostRecentTab();
+
+  // Activate the existing NTP tab for the Start surface.
+  WebStateList* webStateList = browser->GetWebStateList();
+  for (int i = 0; i < webStateList->count(); i++) {
+    web::WebState* webState = webStateList->GetWebStateAt(i);
+    if (IsURLNtp(webState->GetVisibleURL())) {
+      NewTabPageTabHelper::FromWebState(webState)->SetShowStartSurface(true);
+      webStateList->ActivateWebStateAt(i);
+      return;
+    }
+  }
+
+  // Create a new NTP since there is no existing one.
+  TabInsertionBrowserAgent* insertion_agent =
+      TabInsertionBrowserAgent::FromBrowser(browser);
+  web::NavigationManager::WebLoadParams params((GURL(kChromeUINewTabURL)));
+  insertion_agent->InsertWebState(
+      params, nullptr, /*opened_by_dom=*/false,
+      TabInsertion::kPositionAutomatically, /*in_background=*/false,
+      /*inherit_opener=*/false, /*should_show_start_surface=*/true);
+}
+
 // Removes duplicate NTP tabs in |browser|'s WebStateList.
 - (void)removeExcessNTPsInBrowser:(Browser*)browser {
   WebStateList* webStateList = browser->GetWebStateList();
diff --git a/ios/chrome/browser/url_loading/url_loading_browser_agent.mm b/ios/chrome/browser/url_loading/url_loading_browser_agent.mm
index dbff879a871184..fc4a009d3d59c0 100644
--- a/ios/chrome/browser/url_loading/url_loading_browser_agent.mm
+++ b/ios/chrome/browser/url_loading/url_loading_browser_agent.mm
@@ -397,7 +397,8 @@ NOINLINE void InduceBrowserCrash(const GURL& url) {
 
   web::WebState* web_state = insertion_agent->InsertWebState(
       params.web_params, parent_web_state, /*opened_by_dom=*/false,
-      insertion_index, params.in_background(), params.inherit_opener);
+      insertion_index, params.in_background(), params.inherit_opener,
+      /*should_show_start_surface=*/false);
   web_state->GetNavigationManager()->LoadIfNecessary();
   notifier_->NewTabDidLoadUrl(params.web_params.url, params.user_initiated);
 }
diff --git a/ios/chrome/browser/web/web_state_delegate_browser_agent.mm b/ios/chrome/browser/web/web_state_delegate_browser_agent.mm
index 8f3bcad5d160b8..93425ead34dc89 100644
--- a/ios/chrome/browser/web/web_state_delegate_browser_agent.mm
+++ b/ios/chrome/browser/web/web_state_delegate_browser_agent.mm
@@ -205,7 +205,7 @@ void OnHTTPAuthOverlayFinished(web::WebStateDelegate::AuthCallback callback,
       return tab_insertion_agent_->InsertWebState(
           load_params, source, false, TabInsertion::kPositionAutomatically,
           (params.disposition == WindowOpenDisposition::NEW_BACKGROUND_TAB),
-          /*inherit_opener=*/false);
+          /*inherit_opener=*/false, /*should_show_start_surface=*/false);
     }
     case WindowOpenDisposition::CURRENT_TAB: {
       source->GetNavigationManager()->LoadURLWithParams(load_params);
@@ -214,7 +214,8 @@ void OnHTTPAuthOverlayFinished(web::WebStateDelegate::AuthCallback callback,
     case WindowOpenDisposition::NEW_POPUP: {
       return tab_insertion_agent_->InsertWebState(
           load_params, source, true, TabInsertion::kPositionAutomatically,
-          /*in_background=*/false, /*inherit_opener=*/false);
+          /*in_background=*/false, /*inherit_opener=*/false,
+          /*should_show_start_surface=*/false);
     }
     default:
       NOTIMPLEMENTED();
diff --git a/ios/chrome/browser/web_state_list/BUILD.gn b/ios/chrome/browser/web_state_list/BUILD.gn
index 481aa1d25aa850..9220b1c6d497d5 100644
--- a/ios/chrome/browser/web_state_list/BUILD.gn
+++ b/ios/chrome/browser/web_state_list/BUILD.gn
@@ -78,6 +78,7 @@ source_set("agents") {
     "//ios/chrome/browser/browser_state_metrics",
     "//ios/chrome/browser/crash_report",
     "//ios/chrome/browser/main:public",
+    "//ios/chrome/browser/ntp",
     "//ios/chrome/browser/sessions:restoration_agent",
     "//ios/chrome/browser/sessions:restoration_observer",
     "//ios/chrome/browser/snapshots",
diff --git a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h
index 6163945244d2c8..3e23aba7bbaf80 100644
--- a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h
+++ b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h
@@ -37,7 +37,8 @@ class TabInsertionBrowserAgent
       bool opened_by_dom,
       int index,
       bool in_background,
-      bool inherit_opener);
+      bool inherit_opener,
+      bool should_show_start_surface);
 
   web::WebState* InsertWebStateOpenedByDOM(web::WebState* parent);
 
diff --git a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.mm b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.mm
index d0b5e143f512bb..4912268f1edaa9 100644
--- a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.mm
+++ b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent.mm
@@ -5,6 +5,7 @@
 #import "ios/chrome/browser/web_state_list/tab_insertion_browser_agent.h"
 
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
 #import "ios/chrome/browser/web_state_list/web_state_list.h"
 #import "ios/chrome/browser/web_state_list/web_state_opener.h"
 #import "ios/web/public/web_state.h"
@@ -27,7 +28,8 @@
     bool opened_by_dom,
     int index,
     bool in_background,
-    bool inherit_opener) {
+    bool inherit_opener,
+    bool should_show_start_surface) {
   DCHECK(index == TabInsertion::kPositionAutomatically ||
          (index >= 0 && index <= web_state_list_->count()));
 
@@ -56,6 +58,11 @@
 
   std::unique_ptr<web::WebState> web_state =
       web::WebState::Create(create_params);
+  if (should_show_start_surface) {
+    NewTabPageTabHelper::CreateForWebState(web_state.get());
+    NewTabPageTabHelper::FromWebState(web_state.get())
+        ->SetShowStartSurface(true);
+  }
   web_state->GetNavigationManager()->LoadURLWithParams(params);
 
   int inserted_index =
diff --git a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent_unittest.mm b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent_unittest.mm
index e415eaa80e6804..65e02573bb9e60 100644
--- a/ios/chrome/browser/web_state_list/tab_insertion_browser_agent_unittest.mm
+++ b/ios/chrome/browser/web_state_list/tab_insertion_browser_agent_unittest.mm
@@ -53,35 +53,43 @@
 }  // namespace
 
 TEST_F(TabInsertionBrowserAgentTest, InsertUrlSingle) {
-  web::WebState* web_state = agent_->InsertWebState(Params(GURL(kURL1)),
-                                                    /*parent=*/nil,
-                                                    /*opened_by_dom=*/false,
-                                                    /*index=*/0,
-                                                    /*in_background=*/false,
-                                                    /*inherit_opener=*/false);
+  web::WebState* web_state =
+      agent_->InsertWebState(Params(GURL(kURL1)),
+                             /*parent=*/nil,
+                             /*opened_by_dom=*/false,
+                             /*index=*/0,
+                             /*in_background=*/false,
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   ASSERT_EQ(1, browser_->GetWebStateList()->count());
   EXPECT_EQ(web_state, browser_->GetWebStateList()->GetWebStateAt(0));
 }
 
 TEST_F(TabInsertionBrowserAgentTest, InsertUrlMultiple) {
-  web::WebState* web_state0 = agent_->InsertWebState(Params(GURL(kURL1)),
-                                                     /*parent=*/nil,
-                                                     /*opened_by_dom=*/false,
-                                                     /*index=*/0,
-                                                     /*in_background=*/false,
-                                                     /*inherit_opener=*/false);
-  web::WebState* web_state1 = agent_->InsertWebState(Params(GURL(kURL1)),
-                                                     /*parent=*/nil,
-                                                     /*opened_by_dom=*/false,
-                                                     /*index=*/0,
-                                                     /*in_background=*/false,
-                                                     /*inherit_opener=*/false);
-  web::WebState* web_state2 = agent_->InsertWebState(Params(GURL(kURL1)),
-                                                     /*parent=*/nil,
-                                                     /*opened_by_dom=*/false,
-                                                     /*index=*/1,
-                                                     /*in_background=*/false,
-                                                     /*inherit_opener=*/false);
+  web::WebState* web_state0 =
+      agent_->InsertWebState(Params(GURL(kURL1)),
+                             /*parent=*/nil,
+                             /*opened_by_dom=*/false,
+                             /*index=*/0,
+                             /*in_background=*/false,
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
+  web::WebState* web_state1 =
+      agent_->InsertWebState(Params(GURL(kURL1)),
+                             /*parent=*/nil,
+                             /*opened_by_dom=*/false,
+                             /*index=*/0,
+                             /*in_background=*/false,
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
+  web::WebState* web_state2 =
+      agent_->InsertWebState(Params(GURL(kURL1)),
+                             /*parent=*/nil,
+                             /*opened_by_dom=*/false,
+                             /*index=*/1,
+                             /*in_background=*/false,
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
 
   ASSERT_EQ(3, browser_->GetWebStateList()->count());
   EXPECT_EQ(web_state1, browser_->GetWebStateList()->GetWebStateAt(0));
@@ -96,7 +104,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
 
   ASSERT_EQ(1, browser_->GetWebStateList()->count());
   EXPECT_EQ(web_state, browser_->GetWebStateList()->GetWebStateAt(0));
@@ -109,21 +118,24 @@
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   web::WebState* web_state1 =
       agent_->InsertWebState(Params(GURL(kURL1)),
                              /*parent=*/nil,
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   web::WebState* web_state2 =
       agent_->InsertWebState(Params(GURL(kURL1)),
                              /*parent=*/nil,
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
 
   ASSERT_EQ(3, browser_->GetWebStateList()->count());
   EXPECT_EQ(web_state0, browser_->GetWebStateList()->GetWebStateAt(0));
@@ -139,19 +151,22 @@
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   agent_->InsertWebState(Params(GURL(kURL1)),
                          /*parent=*/nil,
                          /*opened_by_dom=*/false,
                          /*index=*/browser_->GetWebStateList()->count(),
                          /*in_background=*/false,
-                         /*inherit_opener=*/false);
+                         /*inherit_opener=*/false,
+                         /*should_show_start_surface=*/false);
   agent_->InsertWebState(Params(GURL(kURL1)),
                          /*parent=*/nil,
                          /*opened_by_dom=*/false,
                          /*index=*/browser_->GetWebStateList()->count(),
                          /*in_background=*/false,
-                         /*inherit_opener=*/false);
+                         /*inherit_opener=*/false,
+                         /*should_show_start_surface=*/false);
 
   // Add a new tab, it should be added behind the parent.
   web::WebState* child =
@@ -160,7 +175,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/TabInsertion::kPositionAutomatically,
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(parent), 0);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(child), 1);
 
@@ -171,7 +187,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/TabInsertion::kPositionAutomatically,
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(web_state),
             browser_->GetWebStateList()->count() - 1);
 
@@ -182,7 +199,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/browser_->GetWebStateList()->count(),
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(web_state2),
             browser_->GetWebStateList()->count() - 1);
 
@@ -193,7 +211,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/TabInsertion::kPositionAutomatically,
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(web_state3),
             browser_->GetWebStateList()->GetIndexOfWebState(web_state) + 1);
 
@@ -204,7 +223,8 @@
                              /*opened_by_dom=*/false,
                              /*index=*/TabInsertion::kPositionAutomatically,
                              /*in_background=*/false,
-                             /*inherit_opener=*/false);
+                             /*inherit_opener=*/false,
+                             /*should_show_start_surface=*/false);
   EXPECT_EQ(browser_->GetWebStateList()->GetIndexOfWebState(web_state4),
             browser_->GetWebStateList()->GetIndexOfWebState(web_state3) + 1);
 }
diff --git a/ios/chrome/browser/web_state_list/view_source_browser_agent.mm b/ios/chrome/browser/web_state_list/view_source_browser_agent.mm
index 1c82828e4e47f6..4866538ca6af80 100644
--- a/ios/chrome/browser/web_state_list/view_source_browser_agent.mm
+++ b/ios/chrome/browser/web_state_list/view_source_browser_agent.mm
@@ -66,5 +66,6 @@
       TabInsertionBrowserAgent::FromBrowser(browser_);
   insertionAgent->InsertWebState(
       loadParams, web_state, true, TabInsertion::kPositionAutomatically,
-      /*in_background=*/false, /*inherit_opener=*/false);
+      /*in_background=*/false, /*inherit_opener=*/false,
+      /*should_show_start_surface=*/false);
 }
diff --git a/ios/chrome/test/app/BUILD.gn b/ios/chrome/test/app/BUILD.gn
index 9ab213fa27a61f..36a8326536bf28 100644
--- a/ios/chrome/test/app/BUILD.gn
+++ b/ios/chrome/test/app/BUILD.gn
@@ -76,7 +76,7 @@ source_set("test_support") {
     "//ios/chrome/browser/ui/browser_view",
     "//ios/chrome/browser/ui/commands",
     "//ios/chrome/browser/ui/main",
-    "//ios/chrome/browser/ui/main:scene",
+    "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/main:scene_testing",
     "//ios/chrome/browser/ui/settings",
     "//ios/chrome/browser/ui/settings:settings_root",