diff --git a/changelog.d/5503.misc b/changelog.d/5503.misc
new file mode 100644
index 0000000000..66deb33684
--- /dev/null
+++ b/changelog.d/5503.misc
@@ -0,0 +1 @@
+[Threads] - Threads Labs Flag is enabled by default and forced to be enabled for existing users, but sill can be disabled manually
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/MatrixConfiguration.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/MatrixConfiguration.kt
index 00d74ab446..8c2296accb 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/MatrixConfiguration.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/MatrixConfiguration.kt
@@ -66,7 +66,7 @@ data class MatrixConfiguration(
         /**
          * Thread messages default enable/disabled value.
          */
-        val threadMessagesEnabledDefault: Boolean = false,
+        val threadMessagesEnabledDefault: Boolean = true,
         /**
          * List of network interceptors, they will be added when building an OkHttp client.
          */
diff --git a/vector-config/src/main/res/values/config-settings.xml b/vector-config/src/main/res/values/config-settings.xml
index ad9c16c214..a8695eed44 100755
--- a/vector-config/src/main/res/values/config-settings.xml
+++ b/vector-config/src/main/res/values/config-settings.xml
@@ -39,7 +39,7 @@
     <!-- Level 1: Labs -->
     <bool name="settings_labs_deferred_dm_visible">true</bool>
     <bool name="settings_labs_deferred_dm_default">true</bool>
-    <bool name="settings_labs_thread_messages_default">false</bool>
+    <bool name="settings_labs_thread_messages_default">true</bool>
     <bool name="settings_labs_new_app_layout_default">true</bool>
     <bool name="settings_labs_new_session_manager_default">false</bool>
     <bool name="settings_labs_new_session_manager_visible">true</bool>
diff --git a/vector/src/main/java/im/vector/app/features/home/HomeActivityViewModel.kt b/vector/src/main/java/im/vector/app/features/home/HomeActivityViewModel.kt
index a54ce2cff3..8f16121a30 100644
--- a/vector/src/main/java/im/vector/app/features/home/HomeActivityViewModel.kt
+++ b/vector/src/main/java/im/vector/app/features/home/HomeActivityViewModel.kt
@@ -254,6 +254,12 @@ class HomeActivityViewModel @AssistedInject constructor(
 //        }
 
         when {
+            !vectorPreferences.areThreadMessagesEnabled() && !vectorPreferences.wasThreadFlagChangedManually() -> {
+                vectorPreferences.setThreadMessagesEnabled()
+                lightweightSettingsStorage.setThreadMessagesEnabled(vectorPreferences.areThreadMessagesEnabled())
+                // Clear Cache
+                _viewEvents.post(HomeActivityViewEvents.MigrateThreads(checkSession = false))
+            }
             // Notify users
             vectorPreferences.shouldNotifyUserAboutThreads() && vectorPreferences.areThreadMessagesEnabled() -> {
                 Timber.i("----> Notify users about threads")
diff --git a/vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt b/vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt
index d46b819cce..2d5fb351f9 100755
--- a/vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt
+++ b/vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt
@@ -239,6 +239,7 @@ class VectorPreferences @Inject constructor(
 
         // This key will be used to identify clients with the new thread support enabled m.thread
         const val SETTINGS_LABS_ENABLE_THREAD_MESSAGES = "SETTINGS_LABS_ENABLE_THREAD_MESSAGES_FINAL"
+        const val SETTINGS_LABS_THREAD_MESSAGES_CHANGED_BY_USER = "SETTINGS_LABS_THREAD_MESSAGES_CHANGED_BY_USER"
         const val SETTINGS_THREAD_MESSAGES_SYNCED = "SETTINGS_THREAD_MESSAGES_SYNCED"
 
         // This key will be used to enable user for displaying live user info or not.
@@ -1129,6 +1130,24 @@ class VectorPreferences @Inject constructor(
                 .apply()
     }
 
+    /**
+     * Indicates whether or not user changed threads flag manually. We need this to not force flag to be enabled on app start.
+     * Should be removed when Threads flag will be removed
+     */
+    fun wasThreadFlagChangedManually(): Boolean {
+        return defaultPrefs.getBoolean(SETTINGS_LABS_THREAD_MESSAGES_CHANGED_BY_USER, false)
+    }
+
+    /**
+     * Sets the flag to indicate that user changed threads flag (e.g. disabled them).
+     */
+    fun setThreadFlagChangedManually() {
+        defaultPrefs
+                .edit()
+                .putBoolean(SETTINGS_LABS_THREAD_MESSAGES_CHANGED_BY_USER, true)
+                .apply()
+    }
+
     /**
      * Indicates whether or not the user will be notified about the new thread support.
      * We should notify the user only if he had old thread support enabled.
diff --git a/vector/src/main/java/im/vector/app/features/settings/labs/VectorSettingsLabsFragment.kt b/vector/src/main/java/im/vector/app/features/settings/labs/VectorSettingsLabsFragment.kt
index c10411301f..189d55d990 100644
--- a/vector/src/main/java/im/vector/app/features/settings/labs/VectorSettingsLabsFragment.kt
+++ b/vector/src/main/java/im/vector/app/features/settings/labs/VectorSettingsLabsFragment.kt
@@ -141,6 +141,7 @@ class VectorSettingsLabsFragment :
      */
     private fun onThreadsPreferenceClicked() {
         // We should migrate threads only if threads are disabled
+        vectorPreferences.setThreadFlagChangedManually()
         vectorPreferences.setShouldMigrateThreads(!vectorPreferences.areThreadMessagesEnabled())
         lightweightSettingsStorage.setThreadMessagesEnabled(vectorPreferences.areThreadMessagesEnabled())
         displayLoadingView()