diff --git a/exportcsv.php b/exportcsv.php
index 6507d6bc296de899a3c5bf24e2b6f76d3740b75f..c60b7ffff7b9dd6b1589335b116aa971ac259c53 100644
--- a/exportcsv.php
+++ b/exportcsv.php
@@ -73,6 +73,7 @@ $slots = $pollService->allSlotsByPoll($poll);
 $votes = $pollService->allVotesByPollId($poll_id);
 
 // CSV header
+echo "\xEF\xBB\xBF"; // BOM character for UTF-8
 if ($poll->format === 'D') {
     $titles_line = ',';
     $moments_line = ',';