diff --git a/R/add_header_above.R b/R/add_header_above.R
index 5231c7f..bf99378 100644
--- a/R/add_header_above.R
+++ b/R/add_header_above.R
@@ -68,6 +68,7 @@
   xml_add_child(kable_xml_thead, new_header_row, .where = 0)
   out <- as_kable_xml(kable_xml)
   attributes(out) <- kable_attrs
+  if (!"kableExtra" %in% class(out)) class(out) <- c("kableExtra", class(out))
   return(out)
 }