diff --git a/src/calibre/gui2/email.py b/src/calibre/gui2/email.py
index 68504245ec..af6831bda9 100644
--- a/src/calibre/gui2/email.py
+++ b/src/calibre/gui2/email.py
@@ -440,6 +440,10 @@ class EmailMixin:  # {{{
                         os.path.splitext(f)[1][1:].upper())
                 if mi.comments and gprefs['add_comments_to_email']:
                     from calibre.utils.html2text import html2text
+                    from calibre.ebooks.metadata import fmt_sidx
+                    if mi.series:
+                        sidx=fmt_sidx(1.0 if mi.series_index is None else mi.series_index, use_roman=config['use_roman_numerals_for_series_number'])
+                        texts[-1] += '\n\n' + _('{series_index} of {series}').format(series_index=sidx, series=mi.series)
                     texts[-1] += '\n\n' + _('About this book:') + '\n\n' + textwrap.fill(html2text(mi.comments))
                 if is_for_kindle(to):
                     prefix = str(newmi.title or t)