diff --git a/lnwire/onion_error.go b/lnwire/onion_error.go
index 961373b9..c6235552 100644
--- a/lnwire/onion_error.go
+++ b/lnwire/onion_error.go
@@ -80,6 +80,7 @@ const (
 	CodeFinalIncorrectHtlcAmount         FailCode = 19
 	CodeExpiryTooFar                     FailCode = 21
 	CodeInvalidOnionPayload                       = FlagPerm | 22
+	CodeMPPTimeout                       FailCode = 23
 )
 
 // String returns the string representation of the failure code.
@@ -154,6 +155,9 @@ func (c FailCode) String() string {
 	case CodeInvalidOnionPayload:
 		return "InvalidOnionPayload"
 
+	case CodeMPPTimeout:
+		return "MPPTimeout"
+
 	default:
 		return "<unknown>"
 	}
@@ -1182,6 +1186,26 @@ func (f *InvalidOnionPayload) Encode(w io.Writer, pver uint32) error {
 	return WriteElements(w, f.Offset)
 }
 
+// FailMPPTimeout is returned if the complete amount for a multi part payment
+// was not received within a reasonable time.
+//
+// NOTE: May only be returned by the final node in the path.
+type FailMPPTimeout struct{}
+
+// Code returns the failure unique code.
+//
+// NOTE: Part of the FailureMessage interface.
+func (f *FailMPPTimeout) Code() FailCode {
+	return CodeMPPTimeout
+}
+
+// Returns a human readable string describing the target FailureMessage.
+//
+// NOTE: Implements the error interface.
+func (f *FailMPPTimeout) Error() string {
+	return f.Code().String()
+}
+
 // DecodeFailure decodes, validates, and parses the lnwire onion failure, for
 // the provided protocol version.
 func DecodeFailure(r io.Reader, pver uint32) (FailureMessage, error) {
@@ -1366,6 +1390,9 @@ func makeEmptyOnionError(code FailCode) (FailureMessage, error) {
 	case CodeInvalidOnionPayload:
 		return &InvalidOnionPayload{}, nil
 
+	case CodeMPPTimeout:
+		return &FailMPPTimeout{}, nil
+
 	default:
 		return nil, errors.Errorf("unknown error code: %v", code)
 	}
diff --git a/lnwire/onion_error_test.go b/lnwire/onion_error_test.go
index 5dafcedd..3ec147d1 100644
--- a/lnwire/onion_error_test.go
+++ b/lnwire/onion_error_test.go
@@ -38,6 +38,7 @@ var onionFailures = []FailureMessage{
 	&FailUnknownNextPeer{},
 	&FailIncorrectPaymentAmount{},
 	&FailFinalExpiryTooSoon{},
+	&FailMPPTimeout{},
 
 	NewFailIncorrectDetails(99, 100),
 	NewInvalidOnionVersion(testOnionHash),