diff --git a/src/fileio.c b/src/fileio.c
index f8b384b..a45ec2c 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -6897,6 +6897,7 @@
 	    && buf->b_mtime != 0
 	    && ((stat_res = mch_stat((char *)buf->b_ffname, &st)) < 0
 		|| time_differs((long)st.st_mtime, buf->b_mtime)
+		|| st.st_size != buf->b_orig_size
 #ifdef HAVE_ST_MODE
 		|| (int)st.st_mode != buf->b_orig_mode
 #else