diff --git a/buffer.py b/buffer.py
index aa28cdb..0125422 100644
--- a/buffer.py
+++ b/buffer.py
@@ -596,8 +596,9 @@ class FileBuffer(Buffer):
             data = ''
 
         if data.startswith('\xEF\xBB\xBF'):
-            self.bytemark = data[:2]
-            data          = data[2:]
+            # utf-8
+            self.bytemark = data[:3]
+            data          = data[3:]
 
         self.nl = self._detect_nl_type(data)
         data = self.read_filter(data)