diff --git a/app/brave_generated_resources.grd b/app/brave_generated_resources.grd
index 92ad474efdaa..bc140e7af757 100644
--- a/app/brave_generated_resources.grd
+++ b/app/brave_generated_resources.grd
@@ -1650,6 +1650,20 @@ Are you sure you want to do this?
       <message name="IDS_FIRSTRUN_DLG_COMPLETE_INSTALLATION_LABEL_BRAVE" desc="Label at top of Dialog noting what's going to happen">
         To ensure the best privacy online, consider setting Brave as the default browser on your computer. With Brave as default, any web link you click will open with Brave's privacy protections.
       </message>
+      <if expr="is_win">
+        <message name="IDS_FIRSTRUN_DLG_WIN_HEADER_TEXT" desc="Text for FirstRun dialog header">
+          Ready for the best privacy online?
+        </message>
+        <message name="IDS_FIRSTRUN_DLG_WIN_CONTENTS_TEXT" desc="Text for FirstRun dialog contents">
+          Set Brave as your default browser to get Brave's privacy protections on every web page you open.
+        </message>
+        <message name="IDS_FIRSTRUN_DLG_WIN_OK_BUTTON_LABEL" desc="Text for FirstRun dialog ok button">
+          Set Brave as default
+        </message>
+        <message name="IDS_FIRSTRUN_DLG_WIN_CANCEL_BUTTON_LABEL" desc="Text for FirstRun dialog cancel button">
+          Maybe later
+        </message>
+      </if>
       <message name="IDS_SETTINGS_WALLET_NETWORKS_ITEM" desc="The label for opening wallet networks list">
         Networks
       </message>
diff --git a/browser/ui/BUILD.gn b/browser/ui/BUILD.gn
index 56b946489655..ffbab5c2c0bb 100644
--- a/browser/ui/BUILD.gn
+++ b/browser/ui/BUILD.gn
@@ -182,6 +182,15 @@ source_set("ui") {
       "views/web_discovery_dialog_view.h",
     ]
 
+    # Use different FirstRun dialog UI on Win.
+    # Upstream only includes it on mac/Linux.
+    if (is_win) {
+      sources += [
+        "views/first_run_dialog_win.cc",
+        "views/first_run_dialog_win.h",
+      ]
+    }
+
     if (use_aura) {
       sources += [
         "views/renderer_context_menu/brave_render_view_context_menu_views.cc",
diff --git a/browser/ui/views/first_run_dialog_win.cc b/browser/ui/views/first_run_dialog_win.cc
new file mode 100644
index 000000000000..ad7a75cf0da1
--- /dev/null
+++ b/browser/ui/views/first_run_dialog_win.cc
@@ -0,0 +1,111 @@
+/* Copyright (c) 2022 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 http://mozilla.org/MPL/2.0/. */
+
+#include "brave/browser/ui/views/first_run_dialog_win.h"
+
+#include <memory>
+#include <utility>
+
+#include "base/bind.h"
+#include "base/memory/scoped_refptr.h"
+#include "base/run_loop.h"
+#include "brave/browser/brave_shell_integration.h"
+#include "brave/grit/brave_generated_resources.h"
+#include "chrome/browser/first_run/first_run.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/metadata/metadata_impl_macros.h"
+#include "ui/gfx/font.h"
+#include "ui/gfx/geometry/insets.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/box_layout.h"
+#include "ui/views/window/dialog_delegate.h"
+
+namespace first_run {
+
+void ShowFirstRunDialog(Profile* profile) {
+  base::RunLoop run_loop(base::RunLoop::Type::kNestableTasksAllowed);
+  FirstRunDialogWin::Show(run_loop.QuitClosure());
+  run_loop.Run();
+}
+
+}  // namespace first_run
+
+// static
+void FirstRunDialogWin::Show(base::RepeatingClosure quit_runloop) {
+  FirstRunDialogWin* dialog = new FirstRunDialogWin(std::move(quit_runloop));
+  views::DialogDelegate::CreateDialogWidget(dialog, NULL, NULL)->Show();
+}
+
+FirstRunDialogWin::FirstRunDialogWin(base::RepeatingClosure quit_runloop)
+    : quit_runloop_(quit_runloop) {
+  set_should_ignore_snapping(true);
+  SetButtonLabel(
+      ui::DIALOG_BUTTON_OK,
+      l10n_util::GetStringUTF16(IDS_FIRSTRUN_DLG_WIN_OK_BUTTON_LABEL));
+  SetButtonLabel(
+      ui::DIALOG_BUTTON_CANCEL,
+      l10n_util::GetStringUTF16(IDS_FIRSTRUN_DLG_WIN_CANCEL_BUTTON_LABEL));
+  constexpr int kChildSpacing = 16;
+  constexpr int kPadding = 24;
+  constexpr int kTopPadding = 20;
+  constexpr int kBottomPadding = 55;
+
+  SetLayoutManager(std::make_unique<views::BoxLayout>(
+      views::BoxLayout::Orientation::kVertical,
+      gfx::Insets(kTopPadding, kPadding, kBottomPadding, kPadding),
+      kChildSpacing));
+
+  constexpr int kHeaderFontSize = 16;
+  int size_diff =
+      kHeaderFontSize - views::Label::GetDefaultFontList().GetFontSize();
+  views::Label::CustomFont header_font = {
+      views::Label::GetDefaultFontList()
+          .DeriveWithSizeDelta(size_diff)
+          .DeriveWithWeight(gfx::Font::Weight::SEMIBOLD)};
+  auto* header_label = AddChildView(std::make_unique<views::Label>(
+      l10n_util::GetStringUTF16(IDS_FIRSTRUN_DLG_WIN_HEADER_TEXT),
+      header_font));
+  header_label->SetHorizontalAlignment(gfx::ALIGN_LEFT);
+
+  constexpr int kContentFontSize = 15;
+  size_diff =
+      kContentFontSize - views::Label::GetDefaultFontList().GetFontSize();
+  views::Label::CustomFont contents_font = {
+      views::Label::GetDefaultFontList()
+          .DeriveWithSizeDelta(size_diff)
+          .DeriveWithWeight(gfx::Font::Weight::NORMAL)};
+  auto* contents_label = AddChildView(std::make_unique<views::Label>(
+      l10n_util::GetStringUTF16(IDS_FIRSTRUN_DLG_WIN_CONTENTS_TEXT),
+      contents_font));
+  contents_label->SetHorizontalAlignment(gfx::ALIGN_LEFT);
+  contents_label->SetMultiLine(true);
+  constexpr int kMaxWidth = 350;
+  contents_label->SetMaximumWidth(kMaxWidth);
+}
+
+FirstRunDialogWin::~FirstRunDialogWin() = default;
+
+void FirstRunDialogWin::Done() {
+  CHECK(!quit_runloop_.is_null());
+  quit_runloop_.Run();
+}
+
+bool FirstRunDialogWin::Accept() {
+  GetWidget()->Hide();
+
+  base::MakeRefCounted<shell_integration::BraveDefaultBrowserWorker>()
+      ->StartSetAsDefault(base::NullCallback());
+
+  Done();
+  return true;
+}
+
+void FirstRunDialogWin::WindowClosing() {
+  first_run::SetShouldShowWelcomePage();
+  Done();
+}
+
+BEGIN_METADATA(FirstRunDialogWin, views::DialogDelegateView)
+END_METADATA
diff --git a/browser/ui/views/first_run_dialog_win.h b/browser/ui/views/first_run_dialog_win.h
new file mode 100644
index 000000000000..456830a8b0df
--- /dev/null
+++ b/browser/ui/views/first_run_dialog_win.h
@@ -0,0 +1,38 @@
+/* Copyright (c) 2022 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 http://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_BROWSER_UI_VIEWS_FIRST_RUN_DIALOG_WIN_H_
+#define BRAVE_BROWSER_UI_VIEWS_FIRST_RUN_DIALOG_WIN_H_
+
+#include "base/callback.h"
+#include "ui/base/metadata/metadata_header_macros.h"
+#include "ui/views/window/dialog_delegate.h"
+
+class FirstRunDialogWin : public views::DialogDelegateView {
+ public:
+  METADATA_HEADER(FirstRunDialogWin);
+
+  FirstRunDialogWin(const FirstRunDialogWin&) = delete;
+  FirstRunDialogWin& operator=(const FirstRunDialogWin&) = delete;
+
+  static void Show(base::RepeatingClosure quit_runloop);
+
+ private:
+  explicit FirstRunDialogWin(base::RepeatingClosure quit_runloop);
+  ~FirstRunDialogWin() override;
+
+  // This terminates the nested message-loop.
+  void Done();
+
+  // views::DialogDelegate overrides:
+  bool Accept() override;
+
+  // views::WidgetDelegate overrides:
+  void WindowClosing() override;
+
+  base::RepeatingClosure quit_runloop_;
+};
+
+#endif  // BRAVE_BROWSER_UI_VIEWS_FIRST_RUN_DIALOG_WIN_H_
diff --git a/chromium_src/chrome/browser/first_run/first_run_dialog.h b/chromium_src/chrome/browser/first_run/first_run_dialog.h
new file mode 100644
index 000000000000..69e6fef1ba30
--- /dev/null
+++ b/chromium_src/chrome/browser/first_run/first_run_dialog.h
@@ -0,0 +1,27 @@
+/* Copyright (c) 2022 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 http://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FIRST_RUN_FIRST_RUN_DIALOG_H_
+#define BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FIRST_RUN_FIRST_RUN_DIALOG_H_
+
+#include "build/build_config.h"
+
+#include "src/chrome/browser/first_run/first_run_dialog.h"
+
+#if BUILDFLAG(IS_WIN)
+
+class Profile;
+
+namespace first_run {
+
+// Enable first run dialog on Win also.
+// Upstream only uses it for macOS/Linux.
+void ShowFirstRunDialog(Profile* profile);
+
+}  // namespace first_run
+
+#endif  // BUILDFLAG(IS_WIN)
+
+#endif  // BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FIRST_RUN_FIRST_RUN_DIALOG_H_
diff --git a/chromium_src/chrome/browser/first_run/first_run_internal_win.cc b/chromium_src/chrome/browser/first_run/first_run_internal_win.cc
new file mode 100644
index 000000000000..46ecb78f71ea
--- /dev/null
+++ b/chromium_src/chrome/browser/first_run/first_run_internal_win.cc
@@ -0,0 +1,40 @@
+/* Copyright (c) 2022 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 http://mozilla.org/MPL/2.0/. */
+
+#include "chrome/browser/first_run/first_run_dialog.h"
+#include "chrome/browser/first_run/first_run_internal.h"
+
+namespace {
+
+bool ShouldShowFirstRunDialog() {
+#if defined(OFFICIAL_BUILD)
+  return first_run::internal::IsOrganicFirstRun();
+#else
+  return false;
+#endif
+}
+
+}  // namespace
+
+#define DoPostImportPlatformSpecificTasks \
+  DoPostImportPlatformSpecificTasks_ChromiumImpl
+
+#include "src/chrome/browser/first_run/first_run_internal_win.cc"
+
+#undef DoPostImportPlatformSpecificTasks
+
+namespace first_run {
+namespace internal {
+
+void DoPostImportPlatformSpecificTasks(Profile* profile) {
+  if (ShouldShowFirstRunDialog()) {
+    ShowFirstRunDialog(profile);
+  }
+
+  DoPostImportPlatformSpecificTasks_ChromiumImpl(profile);
+}
+
+}  // namespace internal
+}  // namespace first_run
diff --git a/chromium_src/chrome/browser/ui/views/first_run_dialog.cc b/chromium_src/chrome/browser/ui/views/first_run_dialog.cc
index f5328cd1e797..204ab69130c6 100644
--- a/chromium_src/chrome/browser/ui/views/first_run_dialog.cc
+++ b/chromium_src/chrome/browser/ui/views/first_run_dialog.cc
@@ -13,17 +13,13 @@
 #include "build/build_config.h"
 #include "chrome/browser/first_run/first_run.h"
 #include "chrome/browser/first_run/first_run_dialog.h"
-#include "chrome/browser/metrics/metrics_reporting_state.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/shell_integration.h"
 #include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/browser/ui/ui_features.h"
-#include "chrome/browser/ui/views/chrome_layout_provider.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
-#include "components/crash/core/app/breakpad_linux.h"
-#include "components/crash/core/app/crashpad.h"
 #include "components/strings/grit/components_strings.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/metadata/metadata_impl_macros.h"
@@ -37,7 +33,7 @@
 namespace first_run {
 
 void ShowFirstRunDialog(Profile* profile) {
-#if defined(OS_MAC)
+#if BUILDFLAG(IS_MAC)
   if (base::FeatureList::IsEnabled(features::kViewsFirstRunDialog))
     ShowFirstRunDialogViews(profile);
   else