diff --git net/cookies/cookie_monster.cc net/cookies/cookie_monster.cc
index cd7ce8c483362..4e05ca9aa5896 100644
--- net/cookies/cookie_monster.cc
+++ net/cookies/cookie_monster.cc
@@ -681,6 +681,25 @@ void CookieMonster::SetCookieableSchemes(
   MaybeRunCookieCallback(std::move(callback), true);
 }
 
+void CookieMonster::AddCookieableSchemes(
+    const std::vector<std::string>& schemes,
+    SetCookieableSchemesCallback callback) {
+  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
+
+  // Calls to this method will have no effect if made after a WebView or
+  // CookieManager instance has been created.
+  if (initialized_) {
+    MaybeRunCookieCallback(std::move(callback), false);
+    return;
+  }
+
+  if (!schemes.empty()) {
+    cookieable_schemes_.insert(cookieable_schemes_.begin(), schemes.begin(),
+                               schemes.end());
+  }
+  MaybeRunCookieCallback(std::move(callback), true);
+}
+
 // This function must be called before the CookieMonster is used.
 void CookieMonster::SetPersistSessionCookies(bool persist_session_cookies) {
   DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
diff --git net/cookies/cookie_monster.h net/cookies/cookie_monster.h
index 18fed025ee0b2..8d7ed64030ad1 100644
--- net/cookies/cookie_monster.h
+++ net/cookies/cookie_monster.h
@@ -239,6 +239,8 @@ class NET_EXPORT CookieMonster : public CookieStore {
   CookieChangeDispatcher& GetChangeDispatcher() override;
   void SetCookieableSchemes(const std::vector<std::string>& schemes,
                             SetCookieableSchemesCallback callback) override;
+  void AddCookieableSchemes(const std::vector<std::string>& schemes,
+                            SetCookieableSchemesCallback callback) override;
   std::optional<bool> SiteHasCookieInOtherPartition(
       const net::SchemefulSite& site,
       const std::optional<CookiePartitionKey>& partition_key) const override;
diff --git net/cookies/cookie_store.h net/cookies/cookie_store.h
index 7c76c93f798b2..09f62ad48ccb4 100644
--- net/cookies/cookie_store.h
+++ net/cookies/cookie_store.h
@@ -171,6 +171,11 @@ class NET_EXPORT CookieStore {
   // Transfer ownership of a CookieAccessDelegate.
   void SetCookieAccessDelegate(std::unique_ptr<CookieAccessDelegate> delegate);
 
+  // Adds to the list of cookieable schemes. Does nothing if called after first
+  // use of the instance (i.e. after the instance initialization process).
+  virtual void AddCookieableSchemes(const std::vector<std::string>& schemes,
+                                    SetCookieableSchemesCallback callback) = 0;
+
   // This may be null if no delegate has been set yet, or the delegate has been
   // reset to null.
   const CookieAccessDelegate* cookie_access_delegate() const {
diff --git services/network/cookie_manager.cc services/network/cookie_manager.cc
index 95f73bcb9fb40..e17a93f69c089 100644
--- services/network/cookie_manager.cc
+++ services/network/cookie_manager.cc
@@ -355,14 +355,9 @@ void CookieManager::AllowFileSchemeCookies(
     AllowFileSchemeCookiesCallback callback) {
   OnSettingsWillChange();
 
-  std::vector<std::string> cookieable_schemes(
-      net::CookieMonster::kDefaultCookieableSchemes,
-      net::CookieMonster::kDefaultCookieableSchemes +
-          net::CookieMonster::kDefaultCookieableSchemesCount);
-  if (allow) {
-    cookieable_schemes.push_back(url::kFileScheme);
-  }
-  cookie_store_->SetCookieableSchemes(cookieable_schemes, std::move(callback));
+  if (!allow)
+    return;
+  cookie_store_->AddCookieableSchemes({url::kFileScheme}, std::move(callback));
 }
 
 void CookieManager::SetForceKeepSessionState() {
diff --git services/network/network_context.cc services/network/network_context.cc
index ca2df1e67d756..d2e963efdf1d8 100644
--- services/network/network_context.cc
+++ services/network/network_context.cc
@@ -2785,22 +2785,26 @@ URLRequestContextOwner NetworkContext::MakeURLRequestContext(
             pref_service.get(), network_service_->network_quality_estimator());
   }
 
-  if (session_cleanup_cookie_store) {
-    // If the pref service was registered and initialized use it.
-    // If not, use nullptr to indicate prefs aren't available.
-    std::unique_ptr<net::CookieMonster> cookie_store =
-        std::make_unique<net::CookieMonster>(
-            session_cleanup_cookie_store.get(), net_log,
-            pref_service
-                ? std::make_unique<KnownLegacyScopeDomainsPrefDelegate>(
-                      pref_service.get())
-                : nullptr);
-    if (params_->persist_session_cookies) {
-      cookie_store->SetPersistSessionCookies(true);
-    }
-
-    builder.SetCookieStore(std::move(cookie_store));
-  }
+  // If the pref service was registered and initialized use it.
+  // If not, use nullptr to indicate prefs aren't available.
+  std::unique_ptr<net::CookieMonster> cookie_store =
+      std::make_unique<net::CookieMonster>(
+          session_cleanup_cookie_store.get(), net_log,
+          pref_service
+              ? std::make_unique<KnownLegacyScopeDomainsPrefDelegate>(
+                    pref_service.get())
+              : nullptr);
+  if (session_cleanup_cookie_store && params_->persist_session_cookies) {
+    cookie_store->SetPersistSessionCookies(true);
+  }
+
+  if (params_->cookieable_schemes.has_value()) {
+    cookie_store->SetCookieableSchemes(
+        *params_->cookieable_schemes,
+        net::CookieStore::SetCookieableSchemesCallback());
+  }
+
+  builder.SetCookieStore(std::move(cookie_store));
 
   base::FilePath transport_security_persister_file_name;
   if (GetFullDataFilePath(params_->file_paths,
diff --git services/network/public/mojom/network_context.mojom services/network/public/mojom/network_context.mojom
index be45c88ba8571..536e92b4e9497 100644
--- services/network/public/mojom/network_context.mojom
+++ services/network/public/mojom/network_context.mojom
@@ -360,6 +360,9 @@ struct NetworkContextParams {
   // cookies. Otherwise it should be false.
   bool persist_session_cookies = false;
 
+  // Schemes that will be passed to CookieMonster::SetCookieableSchemes.
+  array<string>? cookieable_schemes;
+
   // True if an HTTP cache should be used.
   bool http_cache_enabled = true;
   // Maximum size of the HTTP cache. 0 means to use the default size.