diff --git a/app/src/main/java/com/bitchat/android/ui/MediaSendingManager.kt b/app/src/main/java/com/bitchat/android/ui/MediaSendingManager.kt
index 41431cd1..68797e08 100644
--- a/app/src/main/java/com/bitchat/android/ui/MediaSendingManager.kt
+++ b/app/src/main/java/com/bitchat/android/ui/MediaSendingManager.kt
@@ -82,18 +82,42 @@ class MediaSendingManager(
     private var pendingAutomaticTimeoutRequestId: String? = null
 
     /**
-     * Enforce the send-size cap with a user-visible failure.
-     * Returns true if the file is oversized and the send was aborted.
+     * Enforce the send-size cap with a user-visible failure posted to the
+     * conversation the user is sending from. Returns true if the file is
+     * oversized and the send was aborted.
      */
-    private fun rejectIfOversized(file: java.io.File): Boolean {
+    private fun rejectIfOversized(
+        file: java.io.File,
+        toPeerIDOrNull: String?,
+        channelOrNull: String?
+    ): Boolean {
         val size = file.length()
         if (size <= MAX_FILE_SIZE) return false
         Log.e(TAG, "❌ File too large: $size bytes (max: $MAX_FILE_SIZE)")
         val sizeMb = size / (1024 * 1024)
         val maxMb = MAX_FILE_SIZE / (1024 * 1024)
-        messageManager.addSystemMessage(
-            "cannot send ${file.name}: file is too large (${sizeMb} MB, max $maxMb MB)"
-        )
+        val text = "cannot send ${file.name}: file is too large (${sizeMb} MB, max $maxMb MB)"
+        when {
+            toPeerIDOrNull != null -> {
+                val sys = BitchatMessage(
+                    sender = "system",
+                    content = text,
+                    timestamp = Date(),
+                    isRelay = false
+                )
+                messageManager.addPrivateMessageNoUnread(toPeerIDOrNull, sys)
+            }
+            channelOrNull != null -> {
+                val sys = BitchatMessage(
+                    sender = "system",
+                    content = text,
+                    timestamp = Date(),
+                    isRelay = false
+                )
+                messageManager.addChannelMessage(channelOrNull, sys)
+            }
+            else -> messageManager.addSystemMessage(text)
+        }
         return true
     }
 
@@ -119,7 +143,7 @@ class MediaSendingManager(
                     return@withContext null
                 }
 
-                if (rejectIfOversized(file)) {
+                if (rejectIfOversized(file, toPeerIDOrNull, channelOrNull)) {
                     return@withContext null
                 }
 
@@ -163,7 +187,7 @@ class MediaSendingManager(
                     return@withContext null
                 }
 
-                if (rejectIfOversized(file)) {
+                if (rejectIfOversized(file, toPeerIDOrNull, channelOrNull)) {
                     return@withContext null
                 }
 
@@ -207,7 +231,7 @@ class MediaSendingManager(
                     return@withContext null
                 }
 
-                if (rejectIfOversized(file)) {
+                if (rejectIfOversized(file, toPeerIDOrNull, channelOrNull)) {
                     return@withContext null
                 }
 
diff --git a/app/src/test/kotlin/com/bitchat/android/ui/MediaSendingManagerMigrationTest.kt b/app/src/test/kotlin/com/bitchat/android/ui/MediaSendingManagerMigrationTest.kt
index ebe5f744..60c57198 100644
--- a/app/src/test/kotlin/com/bitchat/android/ui/MediaSendingManagerMigrationTest.kt
+++ b/app/src/test/kotlin/com/bitchat/android/ui/MediaSendingManagerMigrationTest.kt
@@ -287,6 +287,43 @@ class MediaSendingManagerMigrationTest {
         assertTrue(messages.none { it.type == com.bitchat.android.model.BitchatMessageType.Image })
     }
 
+    @Test
+    fun `oversized file failure is posted to the private conversation and nothing is sent`() {
+        val bigFile = kotlin.io.path.createTempFile("oversized-private", ".jpg").toFile()
+        try {
+            bigFile.writeBytes(ByteArray(11 * 1024 * 1024) { 0x42 })
+
+            manager.sendImageNote(peerID, null, bigFile.absolutePath)
+
+            val messages = state.privateChats.value[peerID].orEmpty()
+            assertEquals(1, messages.size)
+            assertTrue(messages.single().content.contains("too large"))
+            assertTrue(messages.none { it.type == com.bitchat.android.model.BitchatMessageType.Image })
+            assertTrue(state.getMessagesValue().none { it.content.contains("too large") })
+            verify(mesh, never()).prepareFilePrivate(any(), any(), any(), any())
+        } finally {
+            bigFile.delete()
+        }
+    }
+
+    @Test
+    fun `oversized file failure is posted to the channel and nothing is sent`() {
+        val bigFile = kotlin.io.path.createTempFile("oversized-channel", ".jpg").toFile()
+        try {
+            bigFile.writeBytes(ByteArray(11 * 1024 * 1024) { 0x42 })
+
+            manager.sendImageNote(null, "#test", bigFile.absolutePath)
+
+            val channelMessages = state.getChannelMessagesValue()["#test"].orEmpty()
+            assertEquals(1, channelMessages.size)
+            assertTrue(channelMessages.single().content.contains("too large"))
+            assertTrue(state.getMessagesValue().none { it.content.contains("too large") })
+            verify(mesh, never()).prepareFilePrivate(any(), any(), any(), any())
+        } finally {
+            bigFile.delete()
+        }
+    }
+
     @Test
     fun `cancelled consent cannot later send or echo`() {
         whenever(mesh.prepareFilePrivate(eq(peerID), any(), any(), eq(false)))