diff --git a/beetsplug/convert.py b/beetsplug/convert.py
index af1279299..6f4b3e50e 100644
--- a/beetsplug/convert.py
+++ b/beetsplug/convert.py
@@ -627,6 +627,28 @@ class ConvertPlugin(BeetsPlugin):
                     album, dest, path_formats, pretend, link, hardlink
                 )
 
+        # If the user supplied a playlist name, create a playlist for files
+        # copied to the destination.
+        pl_normpath = None
+        items_paths = None
+        if playlist:
+            _, ext = get_format(fmt)
+            # Playlist paths are understood as relative to the dest directory.
+            pl_normpath = util.normpath(playlist)
+            pl_dir = os.path.dirname(pl_normpath)
+            items_paths = []
+            for item in items:
+                item_path = item.destination(
+                    basedir=dest, path_formats=path_formats
+                )
+
+                # When keeping new files in the library, destination paths
+                # keep original files and extensions.
+                if not opts.keep_new and should_transcode(item, fmt, force):
+                    item_path = replace_ext(item_path, ext)
+
+                items_paths.append(os.path.relpath(item_path, pl_dir))
+
         self._parallel_convert(
             dest,
             opts.keep_new,
@@ -641,20 +663,7 @@ class ConvertPlugin(BeetsPlugin):
         )
 
         if playlist:
-            # Playlist paths are understood as relative to the dest directory.
-            pl_normpath = util.normpath(playlist)
-            pl_dir = os.path.dirname(pl_normpath)
             self._log.info("Creating playlist file {}", pl_normpath)
-            # Generates a list of paths to media files, ensures the paths are
-            # relative to the playlist's location and translates the unicode
-            # strings we get from item.destination to bytes.
-            items_paths = [
-                os.path.relpath(
-                    item.destination(basedir=dest, path_formats=path_formats),
-                    pl_dir,
-                )
-                for item in items
-            ]
             if not pretend:
                 m3ufile = M3UFile(playlist)
                 m3ufile.set_contents(items_paths)
diff --git a/docs/changelog.rst b/docs/changelog.rst
index b7a284587..aa3c65200 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -56,6 +56,8 @@ Bug fixes
 - :ref:`import-cmd` Duplicate detection now works for as-is imports (when
   ``autotag`` is disabled). Previously, ``duplicate_keys`` and
   ``duplicate_action`` config options were silently ignored for as-is imports.
+- :doc:`/plugins/convert`: Fix extension substitution inside path of the
+  exported playlist.
 
 For plugin developers
 ~~~~~~~~~~~~~~~~~~~~~
diff --git a/test/plugins/test_convert.py b/test/plugins/test_convert.py
index 13dbea084..ab3c82248 100644
--- a/test/plugins/test_convert.py
+++ b/test/plugins/test_convert.py
@@ -288,6 +288,26 @@ class ConvertCliTest(ConvertTestCase, ConvertCommand):
         converted = self.convert_dest / "converted.ops"
         assert self.file_endswith(converted, "opus")
 
+    def assert_playlist_entry(self, expected_entry, *args):
+        self.io.addinput("y")
+        self.run_convert(*args, "--playlist", "playlist.m3u8")
+        lines = (self.convert_dest / "playlist.m3u8").read_text().splitlines()
+        assert lines[0] == "#EXTM3U"
+        assert lines[1] == expected_entry
+
+    def test_playlist_entry_uses_config_format(self):
+        self.assert_playlist_entry("converted.mp3")
+
+    def test_playlist_entry_uses_cli_format(self):
+        self.assert_playlist_entry("converted.ops", "--format", "opus")
+
+    def test_playlist_entry_keeps_original_extension_when_not_transcoded(self):
+        self.config["convert"]["no_convert"] = "format:ogg"
+        self.assert_playlist_entry("converted.ogg")
+
+    def test_playlist_entry_keep_new_points_to_destination_file(self):
+        self.assert_playlist_entry("converted.ogg", "--keep-new")
+
 
 @_common.slow_test()
 class NeverConvertLossyFilesTest(ConvertTestCase, ConvertCommand):