diff --git a/message_parsers.hpp b/message_parsers.hpp
index 7d46a88..118da6e 100644
--- a/message_parsers.hpp
+++ b/message_parsers.hpp
@@ -22,6 +22,9 @@
 // RMCP Session Header Size
 constexpr size_t RMCP_SESSION_HEADER_SIZE = 4;
 
+// Maximum payload size
+constexpr size_t MAX_PAYLOAD_SIZE = 255;
+
 enum class SessionHeader
 {
     IPMI15 = 0x00,