diff --git a/src/calibre/ebooks/txt/input.py b/src/calibre/ebooks/txt/input.py
index 2b0245c98b..47b03181f0 100644
--- a/src/calibre/ebooks/txt/input.py
+++ b/src/calibre/ebooks/txt/input.py
@@ -51,6 +51,7 @@ def convert(self, stream, options, file_ext, log,
         html_input = plugin_for_input_format('html')
         for opt in html_input.options:
             setattr(options, opt.option.name, opt.recommended_value)
+        options.input_encoding = 'utf-8'
         base = os.getcwdu()
         if hasattr(stream, 'name'):
             base = os.path.dirname(stream.name)