diff --git a/tests/test_playlist.py b/tests/test_playlist.py
index e581374..3c5a538 100644
--- a/tests/test_playlist.py
+++ b/tests/test_playlist.py
@@ -304,6 +304,104 @@ class TestPlaylistManager:
                 # Verificar URL
                 assert lines[2] == "http://iptv.com/live/user/pass/123.ts"
 
+    def test_write_m3u_uses_epg_channel_id_when_present(self, temp_dir):
+        """Test: _write_m3u usa epg_channel_id en tvg-id cuando está presente."""
+        channel = [
+            {
+                "name": "Test Channel",
+                "stream_id": 123,
+                "stream_icon": "http://icon.com/test.png",
+                "category_id": "5",
+                "epg_channel_id": "test.channel.epg",
+            }
+        ]
+
+        with patch("m3u_list_builder.playlist.PUBLIC_DIR", temp_dir):
+            with patch("m3u_list_builder.playlist.settings") as mock_settings:
+                mock_settings.host = "http://iptv.com"
+                mock_settings.username = "user"
+                mock_settings.password = "pass"
+                mock_settings.output_file = "playlist.m3u"
+                mock_settings.include_text = []
+                mock_settings.exclude_text = []
+
+                from m3u_list_builder.playlist import PlaylistManager
+
+                manager = PlaylistManager()
+                manager._write_m3u(channel)
+
+                output_file = temp_dir / "playlist.m3u"
+                content = output_file.read_text()
+
+                # Debe usar epg_channel_id en tvg-id
+                assert 'tvg-id="test.channel.epg"' in content
+                # El nombre debe seguir apareciendo al final de EXTINF
+                assert ",Test Channel" in content
+
+    def test_write_m3u_falls_back_to_name_when_epg_channel_id_empty(self, temp_dir):
+        """Test: _write_m3u usa name como tvg-id cuando epg_channel_id está vacío."""
+        channel = [
+            {
+                "name": "Fallback Channel",
+                "stream_id": 456,
+                "stream_icon": "",
+                "category_id": "1",
+                "epg_channel_id": "",
+            }
+        ]
+
+        with patch("m3u_list_builder.playlist.PUBLIC_DIR", temp_dir):
+            with patch("m3u_list_builder.playlist.settings") as mock_settings:
+                mock_settings.host = "http://iptv.com"
+                mock_settings.username = "user"
+                mock_settings.password = "pass"
+                mock_settings.output_file = "playlist.m3u"
+                mock_settings.include_text = []
+                mock_settings.exclude_text = []
+
+                from m3u_list_builder.playlist import PlaylistManager
+
+                manager = PlaylistManager()
+                manager._write_m3u(channel)
+
+                output_file = temp_dir / "playlist.m3u"
+                content = output_file.read_text()
+
+                # Debe usar name como fallback en tvg-id
+                assert 'tvg-id="Fallback Channel"' in content
+
+    def test_write_m3u_falls_back_to_name_when_epg_channel_id_missing(self, temp_dir):
+        """Test: _write_m3u usa name como tvg-id cuando epg_channel_id no existe."""
+        channel = [
+            {
+                "name": "No EPG Channel",
+                "stream_id": 789,
+                "stream_icon": "",
+                "category_id": "2",
+                # No epg_channel_id field at all
+            }
+        ]
+
+        with patch("m3u_list_builder.playlist.PUBLIC_DIR", temp_dir):
+            with patch("m3u_list_builder.playlist.settings") as mock_settings:
+                mock_settings.host = "http://iptv.com"
+                mock_settings.username = "user"
+                mock_settings.password = "pass"
+                mock_settings.output_file = "playlist.m3u"
+                mock_settings.include_text = []
+                mock_settings.exclude_text = []
+
+                from m3u_list_builder.playlist import PlaylistManager
+
+                manager = PlaylistManager()
+                manager._write_m3u(channel)
+
+                output_file = temp_dir / "playlist.m3u"
+                content = output_file.read_text()
+
+                # Debe usar name como fallback en tvg-id
+                assert 'tvg-id="No EPG Channel"' in content
+
     def test_write_m3u_missing_fields_uses_defaults(self, temp_dir, minimal_channel):
         """Test: _write_m3u usa valores por defecto para campos faltantes."""
         with patch("m3u_list_builder.playlist.PUBLIC_DIR", temp_dir):