diff --git a/msg_truncate.go b/msg_truncate.go
index 156c5a0e..2ddc9a7d 100644
--- a/msg_truncate.go
+++ b/msg_truncate.go
@@ -8,6 +8,11 @@ package dns
 // record adding as many records as possible without exceeding the
 // requested buffer size.
 //
+// If the message fits within the requested size without compression,
+// Truncate will set the message's Compress attribute to false. It is
+// the caller's responsibility to set it back to true if they wish to
+// compress the payload regardless of size.
+//
 // The TC bit will be set if any records were excluded from the message.
 // If the TC bit is already set on the message it will be retained.
 // TC indicates that the client should retry over TCP.