diff --git a/lisp/ox-ascii.el b/lisp/ox-ascii.el
index 69591e79f..968f297ce 100644
--- a/lisp/ox-ascii.el
+++ b/lisp/ox-ascii.el
@@ -456,7 +456,7 @@ HOW determines the type of justification: it can be `left',
 Empty lines are not indented."
   (when (stringp s)
     (replace-regexp-in-string
-     "\\(^\\)\\(?:.*\\S-\\)" (make-string width ? ) s nil nil 1)))
+     "\\(^\\)[ \t]*\\S-" (make-string width ?\s) s nil nil 1)))
 
 (defun org-ascii--box-string (s info)
   "Return string S with a partial box to its left.