diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index dbf269a5..d9a6b67a 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -580,6 +580,8 @@ This function advances the next thread when finished."
 		      (insert "Incomplete search results (search process was killed).\n"))
 		  (if (eq status 'exit)
 		      (progn
+			(if notmuch-search-process-filter-data
+			    (insert (concat "Error: Unexpected output from notmuch search:\n" notmuch-search-process-filter-data)))
 			(insert "End of search results.")
 			(if (not (= exit-status 0))
 			    (insert (format " (process returned %d)" exit-status)))
diff --git a/test/emacs-large-search-buffer b/test/emacs-large-search-buffer
index 78b3ae8b..a3b5c79c 100755
--- a/test/emacs-large-search-buffer
+++ b/test/emacs-large-search-buffer
@@ -18,10 +18,16 @@ done
 
 notmuch new > /dev/null
 
-test_begin_subtest 'Comparing emacs result to "notmuch search"'
+test_begin_subtest "Ensure that emacs doesn't drop results"
 expected="$(notmuch search '*' | sed -e 's/^thread:[0-9a-f]*  //' -e 's/;//' -e  's/xx*/[BLOB]/')
 End of search results."
 output=$(test_emacs '(notmuch-search "*") (notmuch-test-wait) (message (buffer-string))' 2>&1 | sed -e s',  *, ,g' -e 's/xxx*/[BLOB]/g')
 test_expect_equal "$output" "$expected"
 
+test_begin_subtest "Ensure that emacs doesn't drop error messages"
+output=$(test_emacs '(notmuch-search "--this-option-does-not-exist") (notmuch-test-wait) (message (buffer-string))' 2>&1)
+test_expect_equal "$output" "Error: Unexpected output from notmuch search:
+Unrecognized option: --this-option-does-not-exist
+End of search results. (process returned 1)"
+
 test_done