diff --git a/browser/sync/BUILD.gn b/browser/sync/BUILD.gn
index cea0316b9f10..13db4d313236 100644
--- a/browser/sync/BUILD.gn
+++ b/browser/sync/BUILD.gn
@@ -11,6 +11,7 @@ source_set("sync") {
 
   deps = [
     "//base",
+    "//components/history/core/browser",
     "//components/sync/service",
     "//components/sync_device_info",
   ]
diff --git a/browser/sync/brave_sync_service_impl_delegate.cc b/browser/sync/brave_sync_service_impl_delegate.cc
index bca01058c0c7..1ed07bde8cde 100644
--- a/browser/sync/brave_sync_service_impl_delegate.cc
+++ b/browser/sync/brave_sync_service_impl_delegate.cc
@@ -12,6 +12,7 @@
 #include "base/metrics/histogram_functions.h"
 #include "base/task/single_thread_task_runner.h"
 #include "brave/components/sync/service/brave_sync_service_impl.h"
+#include "components/history/core/browser/history_service.h"
 #include "components/sync_device_info/device_info_sync_service.h"
 #include "components/sync_device_info/device_info_tracker.h"
 #include "components/sync_device_info/local_device_info_provider.h"
@@ -19,8 +20,10 @@
 namespace syncer {
 
 BraveSyncServiceImplDelegate::BraveSyncServiceImplDelegate(
-    DeviceInfoSyncService* device_info_sync_service)
+    DeviceInfoSyncService* device_info_sync_service,
+    history::HistoryService* history_service)
     : device_info_sync_service_(device_info_sync_service),
+      history_service_(history_service),
       weak_ptr_factory_(this) {
   DCHECK(device_info_sync_service_);
 
@@ -99,4 +102,15 @@ void BraveSyncServiceImplDelegate::SetLocalDeviceAppearedCallback(
   local_device_appeared_callback_ = std::move(local_device_appeared_callback);
 }
 
+void BraveSyncServiceImplDelegate::GetKnownToSyncHistoryCount(
+    base::OnceCallback<void(std::pair<bool, int>)> callback) {
+  history_service_->GetKnownToSyncCount(base::BindOnce(
+      [](base::OnceCallback<void(std::pair<bool, int>)> callback,
+         history::HistoryCountResult known_to_sync) {
+        std::move(callback).Run(
+            std::pair(known_to_sync.success, known_to_sync.count));
+      },
+      std::move(callback)));
+}
+
 }  // namespace syncer
diff --git a/browser/sync/brave_sync_service_impl_delegate.h b/browser/sync/brave_sync_service_impl_delegate.h
index 34568186fd74..758dc839875e 100644
--- a/browser/sync/brave_sync_service_impl_delegate.h
+++ b/browser/sync/brave_sync_service_impl_delegate.h
@@ -6,14 +6,17 @@
 #ifndef BRAVE_BROWSER_SYNC_BRAVE_SYNC_SERVICE_IMPL_DELEGATE_H_
 #define BRAVE_BROWSER_SYNC_BRAVE_SYNC_SERVICE_IMPL_DELEGATE_H_
 
-#include "brave/components/sync/service/sync_service_impl_delegate.h"
+#include <utility>
 
 #include "base/memory/raw_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/scoped_observation.h"
+#include "brave/components/sync/service/sync_service_impl_delegate.h"
 #include "components/sync_device_info/device_info_tracker.h"
 
-class Profile;
+namespace history {
+class HistoryService;
+}  // namespace history
 
 namespace syncer {
 
@@ -29,7 +32,8 @@ class BraveSyncServiceImplDelegate
       public syncer::DeviceInfoTracker::Observer {
  public:
   explicit BraveSyncServiceImplDelegate(
-      DeviceInfoSyncService* device_info_sync_service);
+      DeviceInfoSyncService* device_info_sync_service,
+      history::HistoryService* history_service);
   ~BraveSyncServiceImplDelegate() override;
 
   void SuspendDeviceObserverForOwnReset() override;
@@ -38,6 +42,9 @@ class BraveSyncServiceImplDelegate
   void SetLocalDeviceAppearedCallback(
       base::OnceCallback<void()> local_device_appeared_callback) override;
 
+  void GetKnownToSyncHistoryCount(
+      base::OnceCallback<void(std::pair<bool, int>)> callback) override;
+
  private:
   // syncer::DeviceInfoTracker::Observer:
   void OnDeviceInfoChange() override;
@@ -54,6 +61,7 @@ class BraveSyncServiceImplDelegate
       device_info_observer_{this};
 
   raw_ptr<DeviceInfoSyncService> device_info_sync_service_ = nullptr;
+  raw_ptr<history::HistoryService> history_service_ = nullptr;
 
   // This is triggered once after SetLocalDeviceAppearedCallback
   // when the local device first appears in the changed synced devices list
diff --git a/chromium_src/chrome/browser/sync/sync_service_factory.cc b/chromium_src/chrome/browser/sync/sync_service_factory.cc
index ae62180cf4bb..bbd2ade1cb89 100644
--- a/chromium_src/chrome/browser/sync/sync_service_factory.cc
+++ b/chromium_src/chrome/browser/sync/sync_service_factory.cc
@@ -5,13 +5,16 @@
 
 #include "brave/browser/sync/brave_sync_service_impl_delegate.h"
 #include "brave/components/sync/service/brave_sync_service_impl.h"
+#include "chrome/browser/history/history_service_factory.h"
 #include "chrome/browser/sync/device_info_sync_service_factory.h"
 
-#define BRAVE_BUILD_SERVICE_INSTANCE_FOR                      \
-  std::make_unique<syncer::BraveSyncServiceImpl>(             \
-      std::move(init_params),                                 \
-      std::make_unique<syncer::BraveSyncServiceImplDelegate>( \
-          DeviceInfoSyncServiceFactory::GetForProfile(profile)));
+#define BRAVE_BUILD_SERVICE_INSTANCE_FOR                        \
+  std::make_unique<syncer::BraveSyncServiceImpl>(               \
+      std::move(init_params),                                   \
+      std::make_unique<syncer::BraveSyncServiceImplDelegate>(   \
+          DeviceInfoSyncServiceFactory::GetForProfile(profile), \
+          HistoryServiceFactory::GetForProfile(                 \
+              profile, ServiceAccessType::IMPLICIT_ACCESS)));
 
 #include "src/chrome/browser/sync/sync_service_factory.cc"
 
diff --git a/chromium_src/components/history/core/browser/history_backend.cc b/chromium_src/components/history/core/browser/history_backend.cc
new file mode 100644
index 000000000000..1aab3df42c2a
--- /dev/null
+++ b/chromium_src/components/history/core/browser/history_backend.cc
@@ -0,0 +1,15 @@
+/* Copyright (c) 2024 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "src/components/history/core/browser/history_backend.cc"
+
+namespace history {
+
+HistoryCountResult HistoryBackend::GetKnownToSyncCount() {
+  int count = 0;
+  return {db_ && db_->GetKnownToSyncCount(&count), count};
+}
+
+}  // namespace history
diff --git a/chromium_src/components/history/core/browser/history_backend.h b/chromium_src/components/history/core/browser/history_backend.h
new file mode 100644
index 000000000000..57e2754b8502
--- /dev/null
+++ b/chromium_src/components/history/core/browser/history_backend.h
@@ -0,0 +1,17 @@
+/* Copyright (c) 2024 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
+#define BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
+
+#define GetHistoryCount  \
+  GetKnownToSyncCount(); \
+  HistoryCountResult GetHistoryCount
+
+#include "src/components/history/core/browser/history_backend.h"  // IWYU pragma: export
+
+#undef GetHistoryCount
+
+#endif  // BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
diff --git a/chromium_src/components/history/core/browser/history_service.cc b/chromium_src/components/history/core/browser/history_service.cc
new file mode 100644
index 000000000000..1f26dee36973
--- /dev/null
+++ b/chromium_src/components/history/core/browser/history_service.cc
@@ -0,0 +1,18 @@
+/* Copyright (c) 2024 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "src/components/history/core/browser/history_service.cc"
+
+namespace history {
+
+void HistoryService::GetKnownToSyncCount(
+    base::OnceCallback<void(HistoryCountResult)> callback) {
+  backend_task_runner_->PostTaskAndReplyWithResult(
+      FROM_HERE,
+      base::BindOnce(&HistoryBackend::GetKnownToSyncCount, history_backend_),
+      std::move(callback));
+}
+
+}  // namespace history
diff --git a/chromium_src/components/history/core/browser/history_service.h b/chromium_src/components/history/core/browser/history_service.h
index dc919d0f558f..98180ad2a2d1 100644
--- a/chromium_src/components/history/core/browser/history_service.h
+++ b/chromium_src/components/history/core/browser/history_service.h
@@ -15,8 +15,15 @@ class BraveHistoryQuickProviderTest;
   friend class ::BraveHistoryQuickProviderTest; \
   void CleanupUnused
 
+#define AddRelatedSearchesForVisit                                     \
+  GetKnownToSyncCount(                                                 \
+      base::OnceCallback<void(history::HistoryCountResult)> callback); \
+  void AddRelatedSearchesForVisit
+
 #include "src/components/history/core/browser/history_service.h"  // IWYU pragma: export
 
+#undef AddRelatedSearchesForVisit
+
 #undef Cleanup
 
 #endif  // BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_SERVICE_H_
diff --git a/chromium_src/components/history/core/browser/visit_database.cc b/chromium_src/components/history/core/browser/visit_database.cc
index cea9ec61ce37..4072701c13a1 100644
--- a/chromium_src/components/history/core/browser/visit_database.cc
+++ b/chromium_src/components/history/core/browser/visit_database.cc
@@ -13,3 +13,21 @@
 #include "src/components/history/core/browser/visit_database.cc"
 
 #undef SOURCE_SAFARI_IMPORTED
+
+namespace history {
+
+bool VisitDatabase::GetKnownToSyncCount(int* count) {
+  sql::Statement statement(
+      GetDB().GetCachedStatement(SQL_FROM_HERE,
+                                 "SELECT COUNT(*) "
+                                 "FROM visits "
+                                 "WHERE is_known_to_sync == TRUE"));
+
+  *count = 0;
+  if (statement.Step()) {
+    *count = statement.ColumnInt(0);
+  }
+  return true;
+}
+
+}  // namespace history
diff --git a/chromium_src/components/history/core/browser/visit_database.h b/chromium_src/components/history/core/browser/visit_database.h
new file mode 100644
index 000000000000..a2932e49af66
--- /dev/null
+++ b/chromium_src/components/history/core/browser/visit_database.h
@@ -0,0 +1,17 @@
+/* Copyright (c) 2024 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_VISIT_DATABASE_H_
+#define BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_VISIT_DATABASE_H_
+
+#define GetHistoryCount            \
+  GetKnownToSyncCount(int* count); \
+  bool GetHistoryCount
+
+#include "src/components/history/core/browser/visit_database.h"  // IWYU pragma: export
+
+#undef GetHistoryCount
+
+#endif  // BRAVE_CHROMIUM_SRC_COMPONENTS_HISTORY_CORE_BROWSER_VISIT_DATABASE_H_
diff --git a/chromium_src/ios/chrome/browser/sync/model/sync_service_factory.mm b/chromium_src/ios/chrome/browser/sync/model/sync_service_factory.mm
index 64009f9faef4..cc49a0b94f9a 100644
--- a/chromium_src/ios/chrome/browser/sync/model/sync_service_factory.mm
+++ b/chromium_src/ios/chrome/browser/sync/model/sync_service_factory.mm
@@ -5,13 +5,16 @@
 
 #include "brave/browser/sync/brave_sync_service_impl_delegate.h"
 #include "brave/components/sync/service/brave_sync_service_impl.h"
+#include "ios/chrome/browser/history/model/history_service_factory.h"
 #include "ios/chrome/browser/sync/model/device_info_sync_service_factory.h"
 
-#define BRAVE_BUILD_SERVICE_INSTANCE_FOR                      \
-  std::make_unique<syncer::BraveSyncServiceImpl>(             \
-      std::move(init_params),                                 \
-      std::make_unique<syncer::BraveSyncServiceImplDelegate>( \
-          DeviceInfoSyncServiceFactory::GetForBrowserState(browser_state)));
+#define BRAVE_BUILD_SERVICE_INSTANCE_FOR                                   \
+  std::make_unique<syncer::BraveSyncServiceImpl>(                          \
+      std::move(init_params),                                              \
+      std::make_unique<syncer::BraveSyncServiceImplDelegate>(              \
+          DeviceInfoSyncServiceFactory::GetForBrowserState(browser_state), \
+          ios::HistoryServiceFactory::GetForBrowserState(                  \
+              browser_state, ServiceAccessType::IMPLICIT_ACCESS)));
 
 #include "src/ios/chrome/browser/sync/model/sync_service_factory.mm"
 
diff --git a/components/brave_sync/brave_sync_p3a.cc b/components/brave_sync/brave_sync_p3a.cc
index 42faa58cfcbc..0804cf8a5f1c 100644
--- a/components/brave_sync/brave_sync_p3a.cc
+++ b/components/brave_sync/brave_sync_p3a.cc
@@ -46,12 +46,12 @@ void RecordEnabledTypes(bool sync_everything_enabled,
 }
 
 void RecordSyncedObjectsCount(int total_entities) {
-  // "Brave.Sync.SyncedObjectsCount"
+  // "Brave.Sync.SyncedObjectsCount.2"
   // 0 - 0..1000
   // 1 - 1001..10000
   // 2 - 10001..49000
   // 3 - >= 49001
-  p3a_utils::RecordToHistogramBucket(kSyncedObjectsCountHistogramName,
+  p3a_utils::RecordToHistogramBucket(kSyncedObjectsCountHistogramNameV2,
                                      {1000, 10000, 49000}, total_entities);
 }
 
diff --git a/components/brave_sync/brave_sync_p3a.h b/components/brave_sync/brave_sync_p3a.h
index 66bfd68bd3ec..7c216bcbc4dc 100644
--- a/components/brave_sync/brave_sync_p3a.h
+++ b/components/brave_sync/brave_sync_p3a.h
@@ -14,8 +14,9 @@ namespace p3a {
 // TODO(alexeybarabash): move here also "Brave.Sync.Status.2" and
 // "Brave.Sync.ProgressTokenEverReset"
 inline constexpr char kEnabledTypesHistogramName[] = "Brave.Sync.EnabledTypes";
-inline constexpr char kSyncedObjectsCountHistogramName[] =
-    "Brave.Sync.SyncedObjectsCount";
+// Improved version of metric which includes count of synced History objects
+inline constexpr char kSyncedObjectsCountHistogramNameV2[] =
+    "Brave.Sync.SyncedObjectsCount.2";
 
 enum class EnabledTypesAnswer {
   kEmptyOrBookmarksOnly = 0,
diff --git a/components/brave_sync/brave_sync_p3a_unittest.cc b/components/brave_sync/brave_sync_p3a_unittest.cc
index c12af598a5f0..9158476e959a 100644
--- a/components/brave_sync/brave_sync_p3a_unittest.cc
+++ b/components/brave_sync/brave_sync_p3a_unittest.cc
@@ -58,22 +58,22 @@ TEST(BraveSyncP3ATest, TestSyncedObjectsCount) {
   base::HistogramTester histogram_tester;
 
   RecordSyncedObjectsCount(0);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 0, 1);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 0, 1);
   RecordSyncedObjectsCount(1000);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 0, 2);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 0, 2);
 
   RecordSyncedObjectsCount(1001);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 1, 1);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 1, 1);
   RecordSyncedObjectsCount(10000);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 1, 2);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 1, 2);
 
   RecordSyncedObjectsCount(10001);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 2, 1);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 2, 1);
   RecordSyncedObjectsCount(49000);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 2, 2);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 2, 2);
 
   RecordSyncedObjectsCount(49001);
-  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramName, 3, 1);
+  histogram_tester.ExpectBucketCount(kSyncedObjectsCountHistogramNameV2, 3, 1);
 }
 
 }  // namespace p3a
diff --git a/components/history/core/browser/BUILD.gn b/components/history/core/browser/BUILD.gn
new file mode 100644
index 000000000000..0386f7d707e3
--- /dev/null
+++ b/components/history/core/browser/BUILD.gn
@@ -0,0 +1,16 @@
+# Copyright (c) 2024 The Brave Authors. All rights reserved.
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at https://mozilla.org/MPL/2.0/.
+
+source_set("unit_tests") {
+  testonly = true
+  sources = [
+    "//brave/components/history/core/browser/brave_visit_database_unittest.cc",
+  ]
+  deps = [
+    "//base",
+    "//components/history/core/browser",
+    "//testing/gtest",
+  ]
+}
diff --git a/components/history/core/browser/brave_visit_database_unittest.cc b/components/history/core/browser/brave_visit_database_unittest.cc
new file mode 100644
index 000000000000..0c0c05df7fdc
--- /dev/null
+++ b/components/history/core/browser/brave_visit_database_unittest.cc
@@ -0,0 +1,83 @@
+/* Copyright (c) 2024 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "base/time/time.h"
+#include "components/history/core/browser/url_database.h"
+#include "components/history/core/browser/visit_database.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+
+using base::Time;
+
+namespace history {
+
+// Inspired by Chromium's VisitDatabaseTest.IsKnownToSync
+class BraveVisitDatabaseTest : public PlatformTest,
+                               public URLDatabase,
+                               public VisitDatabase {
+ public:
+  BraveVisitDatabaseTest() {}
+
+ private:
+  // Test setup.
+  void SetUp() override {
+    PlatformTest::SetUp();
+
+    EXPECT_TRUE(db_.OpenInMemory());
+
+    // Initialize the tables for this test.
+    CreateURLTable(false);
+    CreateMainURLIndex();
+    InitVisitTable();
+  }
+  void TearDown() override {
+    db_.Close();
+    PlatformTest::TearDown();
+  }
+
+  // Provided for URL/VisitDatabase.
+  sql::Database& GetDB() override { return db_; }
+
+  sql::Database db_;
+};
+
+TEST_F(BraveVisitDatabaseTest, BraveGetKnownToSyncCount) {
+  // Insert three rows, VisitIDs 1, 2, and 3.
+  for (VisitID i = 1; i <= 3; i++) {
+    VisitRow original(i, Time::Now(), 23, ui::PageTransitionFromInt(0), 19,
+                      false, 0);
+    AddVisit(&original, SOURCE_BROWSED);
+    ASSERT_EQ(i, original.visit_id);  // Verifies that we added 1, 2, and 3
+  }
+
+  int known_to_sync_count = 0;
+  ASSERT_TRUE(GetKnownToSyncCount(&known_to_sync_count));
+  EXPECT_EQ(known_to_sync_count, 0);
+
+  // Set 2 and 3 to be `is_known_to_sync`.
+  VisitRow visit2;
+  ASSERT_TRUE(GetRowForVisit(2, &visit2));
+  EXPECT_FALSE(visit2.is_known_to_sync);
+  visit2.is_known_to_sync = true;
+  ASSERT_TRUE(UpdateVisitRow(visit2));
+
+  VisitRow visit3;
+  ASSERT_TRUE(GetRowForVisit(3, &visit3));
+  EXPECT_FALSE(visit3.is_known_to_sync);
+  visit3.is_known_to_sync = true;
+  ASSERT_TRUE(UpdateVisitRow(visit3));
+
+  ASSERT_TRUE(GetKnownToSyncCount(&known_to_sync_count));
+  EXPECT_EQ(known_to_sync_count, 2);
+
+  // Now clear out all `is_known_to_sync` bits and verify that we still count
+  // correctly.
+  SetAllVisitsAsNotKnownToSync();
+
+  ASSERT_TRUE(GetKnownToSyncCount(&known_to_sync_count));
+  EXPECT_EQ(known_to_sync_count, 0);
+}
+
+}  // namespace history
diff --git a/components/p3a/metric_names.h b/components/p3a/metric_names.h
index 63249cdf286a..47833458d292 100644
--- a/components/p3a/metric_names.h
+++ b/components/p3a/metric_names.h
@@ -218,7 +218,7 @@ inline constexpr auto kCollectedSlowHistograms =
     "Brave.ReaderMode.NumberReaderModeActivated",
     "Brave.Rewards.TipsSent.2",
     "Brave.Sync.EnabledTypes",
-    "Brave.Sync.SyncedObjectsCount",
+    "Brave.Sync.SyncedObjectsCount.2",
     "Brave.Today.UsageMonthly",
     "Brave.Toolbar.ForwardNavigationAction",
     "Brave.Wallet.UsageMonthly",
diff --git a/components/sync/service/BUILD.gn b/components/sync/service/BUILD.gn
index b1fc73c29a58..ac9021fc8393 100644
--- a/components/sync/service/BUILD.gn
+++ b/components/sync/service/BUILD.gn
@@ -20,6 +20,7 @@ source_set("unit_tests") {
     "//base/test:test_support",
     "//brave/components/brave_sync:crypto",
     "//brave/components/brave_sync:network_time_helper",
+    "//brave/components/brave_sync:p3a",
     "//brave/components/brave_sync:prefs",
     "//brave/components/constants",
     "//brave/components/sync/test:test_support",
diff --git a/components/sync/service/brave_sync_service_impl.cc b/components/sync/service/brave_sync_service_impl.cc
index 0e641ae64ecb..4d4b1bc21ed5 100644
--- a/components/sync/service/brave_sync_service_impl.cc
+++ b/components/sync/service/brave_sync_service_impl.cc
@@ -323,13 +323,17 @@ void BraveSyncServiceImpl::LocalDeviceAppeared() {
 }
 
 namespace {
-const int kCyclesBeforeUpdateP3AObjects = 10;
+// Typical cycle takes 30 sec, let's send P3A updates each ~30 minutes
+const int kCyclesBeforeUpdateP3AObjects = 60;
+// And Let's do the first update in ~5 minutes after sync start
+const int kCyclesBeforeFirstUpdatesP3A = 10;
 }  // namespace
 
 void BraveSyncServiceImpl::OnSyncCycleCompleted(
     const SyncCycleSnapshot& snapshot) {
   SyncServiceImpl::OnSyncCycleCompleted(snapshot);
-  if (completed_cycles_count_ % kCyclesBeforeUpdateP3AObjects == 0) {
+  if (completed_cycles_count_ == kCyclesBeforeFirstUpdatesP3A ||
+      completed_cycles_count_ % kCyclesBeforeUpdateP3AObjects == 0) {
     UpdateP3AObjectsNumber();
   }
   ++completed_cycles_count_;
@@ -347,7 +351,19 @@ void BraveSyncServiceImpl::OnGotEntityCounts(
     total_entities += count.non_tombstone_entities;
   }
 
-  brave_sync::p3a::RecordSyncedObjectsCount(total_entities);
+  if (GetUserSettings()->GetSelectedTypes().Has(
+          syncer::UserSelectableType::kHistory)) {
+    // History stores info about synced objects in a different way than the
+    // others types. Issue a separate request to achieve this info
+    sync_service_impl_delegate_->GetKnownToSyncHistoryCount(base::BindOnce(
+        [](int total_entities, std::pair<bool, int> known_to_sync_count) {
+          brave_sync::p3a::RecordSyncedObjectsCount(total_entities +
+                                                    known_to_sync_count.second);
+        },
+        total_entities));
+  } else {
+    brave_sync::p3a::RecordSyncedObjectsCount(total_entities);
+  }
 }
 
 void BraveSyncServiceImpl::OnPreferredDataTypesPrefChange(
diff --git a/components/sync/service/brave_sync_service_impl.h b/components/sync/service/brave_sync_service_impl.h
index 9c1fedfc1e23..25dd108e5443 100644
--- a/components/sync/service/brave_sync_service_impl.h
+++ b/components/sync/service/brave_sync_service_impl.h
@@ -78,6 +78,8 @@ class BraveSyncServiceImpl : public SyncServiceImpl {
   FRIEND_TEST_ALL_PREFIXES(BraveSyncServiceImplTest, JoinActiveOrNewChain);
   FRIEND_TEST_ALL_PREFIXES(BraveSyncServiceImplTest, JoinDeletedChain);
   FRIEND_TEST_ALL_PREFIXES(BraveSyncServiceImplTest, HistoryPreconditions);
+  FRIEND_TEST_ALL_PREFIXES(BraveSyncServiceImplTest,
+                           P3aForHistoryThroughDelegate);
 
   BraveSyncAuthManager* GetBraveSyncAuthManager();
   SyncServiceCrypto* GetCryptoForTests();
diff --git a/components/sync/service/brave_sync_service_impl_unittest.cc b/components/sync/service/brave_sync_service_impl_unittest.cc
index 02100ac6eaad..ef51072cf6f5 100644
--- a/components/sync/service/brave_sync_service_impl_unittest.cc
+++ b/components/sync/service/brave_sync_service_impl_unittest.cc
@@ -7,8 +7,11 @@
 
 #include "base/base64.h"
 #include "base/logging.h"
+#include "base/memory/raw_ptr.h"
 #include "base/test/gtest_util.h"
+#include "base/test/metrics/histogram_tester.h"
 #include "base/test/task_environment.h"
+#include "brave/components/brave_sync/brave_sync_p3a.h"
 #include "brave/components/history/core/browser/sync/brave_history_delete_directives_model_type_controller.h"
 #include "brave/components/history/core/browser/sync/brave_history_model_type_controller.h"
 #include "brave/components/sync/service/brave_sync_service_impl.h"
@@ -19,6 +22,7 @@
 #include "components/os_crypt/sync/os_crypt_mocker.h"
 #include "components/sync/engine/nigori/key_derivation_params.h"
 #include "components/sync/engine/nigori/nigori.h"
+#include "components/sync/model/type_entities_count.h"
 #include "components/sync/service/data_type_manager_impl.h"
 #include "components/sync/test/data_type_manager_mock.h"
 #include "components/sync/test/fake_data_type_controller.h"
@@ -65,10 +69,13 @@ class SyncServiceImplDelegateMock : public SyncServiceImplDelegate {
  public:
   SyncServiceImplDelegateMock() = default;
   ~SyncServiceImplDelegateMock() override = default;
-  void SuspendDeviceObserverForOwnReset() override {}
-  void ResumeDeviceObserver() override {}
-  void SetLocalDeviceAppearedCallback(
-      base::OnceCallback<void()> local_device_appeared_callback) override {}
+
+  MOCK_METHOD0(SuspendDeviceObserverForOwnReset, void());
+  MOCK_METHOD0(ResumeDeviceObserver, void());
+  MOCK_METHOD1(SetLocalDeviceAppearedCallback,
+               void(base::OnceCallback<void()>));
+  MOCK_METHOD1(GetKnownToSyncHistoryCount,
+               void(base::OnceCallback<void(std::pair<bool, int>)>));
 };
 
 class SyncServiceObserverMock : public SyncServiceObserver {
@@ -110,9 +117,12 @@ class BraveSyncServiceImplTest : public testing::Test {
     ON_CALL(*sync_client, CreateDataTypeControllers(_))
         .WillByDefault(Return(ByMove(std::move(controllers))));
 
+    auto sync_service_delegate(std::make_unique<SyncServiceImplDelegateMock>());
+    sync_service_delegate_ = sync_service_delegate.get();
+
     sync_service_impl_ = std::make_unique<BraveSyncServiceImpl>(
         sync_service_impl_bundle_.CreateBasicInitParams(std::move(sync_client)),
-        std::make_unique<SyncServiceImplDelegateMock>());
+        std::move(sync_service_delegate));
   }
 
   brave_sync::Prefs* brave_sync_prefs() { return &brave_sync_prefs_; }
@@ -141,6 +151,7 @@ class BraveSyncServiceImplTest : public testing::Test {
 
  protected:
   content::BrowserTaskEnvironment task_environment_;
+  raw_ptr<SyncServiceImplDelegateMock> sync_service_delegate_;
 
  private:
   SyncServiceImplBundle sync_service_impl_bundle_;
@@ -592,4 +603,48 @@ TEST_F(BraveSyncServiceImplTest, OnlyBookmarksAfterSetup) {
   OSCryptMocker::TearDown();
 }
 
+TEST_F(BraveSyncServiceImplTest, P3aForHistoryThroughDelegate) {
+  OSCryptMocker::SetUp();
+  CreateSyncService(ModelTypeSet({BOOKMARKS, HISTORY}));
+
+  brave_sync_service_impl()->Initialize();
+  EXPECT_FALSE(engine());
+  brave_sync_service_impl()->SetSyncCode(kValidSyncCode);
+  task_environment_.RunUntilIdle();
+
+  base::HistogramTester histogram_tester;
+
+  std::vector<syncer::TypeEntitiesCount> counts;
+  syncer::TypeEntitiesCount bookmarks_count(syncer::BOOKMARKS);
+  bookmarks_count.entities = bookmarks_count.non_tombstone_entities = 1;
+  counts.push_back(bookmarks_count);
+
+  brave_sync_service_impl()->OnGotEntityCounts(counts);
+  histogram_tester.ExpectBucketCount(
+      brave_sync::p3a::kSyncedObjectsCountHistogramNameV2, 0, 1);
+
+  // Enable History and pretend we got its number from delegate.
+  // We need to have setup handle, otherwise
+  // |SyncUserSettingsImpl::SetSelectedTypes| and
+  // |SyncUserSettingsImpl::GetSelectedTypes| work wrong
+  auto sync_blocker = brave_sync_service_impl()->GetSetupInProgressHandle();
+  auto selected_types =
+      brave_sync_service_impl()->GetUserSettings()->GetSelectedTypes();
+  selected_types.Put(UserSelectableType::kHistory);
+  brave_sync_service_impl()->GetUserSettings()->SetSelectedTypes(
+      false, selected_types);
+
+  ON_CALL(*sync_service_delegate_, GetKnownToSyncHistoryCount(_))
+      .WillByDefault(
+          [](base::OnceCallback<void(std::pair<bool, int>)> callback) {
+            std::move(callback).Run(std::pair<bool, int>(true, 10001));
+          });
+
+  brave_sync_service_impl()->OnGotEntityCounts(counts);
+  histogram_tester.ExpectBucketCount(
+      brave_sync::p3a::kSyncedObjectsCountHistogramNameV2, 2, 1);
+
+  OSCryptMocker::TearDown();
+}
+
 }  // namespace syncer
diff --git a/components/sync/service/sync_service_impl_delegate.h b/components/sync/service/sync_service_impl_delegate.h
index 937f160aedf3..a39b4d7b03a5 100644
--- a/components/sync/service/sync_service_impl_delegate.h
+++ b/components/sync/service/sync_service_impl_delegate.h
@@ -6,6 +6,8 @@
 #ifndef BRAVE_COMPONENTS_SYNC_SERVICE_SYNC_SERVICE_IMPL_DELEGATE_H_
 #define BRAVE_COMPONENTS_SYNC_SERVICE_SYNC_SERVICE_IMPL_DELEGATE_H_
 
+#include <utility>
+
 #include "base/functional/callback_forward.h"
 #include "base/memory/raw_ptr.h"
 
@@ -22,6 +24,9 @@ class SyncServiceImplDelegate {
   virtual void SetLocalDeviceAppearedCallback(
       base::OnceCallback<void()> local_device_appeared_callback) = 0;
 
+  virtual void GetKnownToSyncHistoryCount(
+      base::OnceCallback<void(std::pair<bool, int>)> callback) = 0;
+
   void set_profile_sync_service(BraveSyncServiceImpl* sync_service_impl) {
     sync_service_impl_ = sync_service_impl;
   }
diff --git a/test/BUILD.gn b/test/BUILD.gn
index fbe5c1c62bbf..b1fd72c30cdc 100644
--- a/test/BUILD.gn
+++ b/test/BUILD.gn
@@ -234,6 +234,7 @@ test("brave_unit_tests") {
     "//brave/components/de_amp/browser/test:unit_tests",
     "//brave/components/debounce/browser/test:unit_tests",
     "//brave/components/embedder_support:unit_tests",
+    "//brave/components/history/core/browser:unit_tests",
     "//brave/components/history/core/browser/sync:unit_tests",
     "//brave/components/ipfs/buildflags",
     "//brave/components/ipfs/test:brave_ipfs_unit_tests",