diff --git a/docs/libcurl/opts/CURLOPT_APPEND.md b/docs/libcurl/opts/CURLOPT_APPEND.md
index 857f88012f..867cace74f 100644
--- a/docs/libcurl/opts/CURLOPT_APPEND.md
+++ b/docs/libcurl/opts/CURLOPT_APPEND.md
@@ -10,6 +10,7 @@ See-also:
   - CURLOPT_UPLOAD (3)
 Protocol:
   - FTP
+  - SFTP
 Added-in: 7.17.0
 ---