diff --git a/mbus/mbus-serial.c b/mbus/mbus-serial.c
index 34e1e8b..71b90c2 100644
--- a/mbus/mbus-serial.c
+++ b/mbus/mbus-serial.c
@@ -280,7 +280,7 @@ mbus_serial_recv_frame(mbus_serial_handle *handle, mbus_frame *frame)
     if (_mbus_recv_event)
         _mbus_recv_event(MBUS_HANDLE_TYPE_SERIAL, buff, len);
       
-    if (remaining < 0)
+    if (remaining != 0)
     {
         // Would be OK when e.g. scanning the bus, otherwise it is a failure.
         // printf("%s: M-Bus layer failed to receive complete data.\n", __PRETTY_FUNCTION__);
diff --git a/mbus/mbus-tcp.c b/mbus/mbus-tcp.c
index 53cfbd1..f29e8ce 100644
--- a/mbus/mbus-tcp.c
+++ b/mbus/mbus-tcp.c
@@ -218,7 +218,7 @@ mbus_tcp_recv_frame(mbus_tcp_handle *handle, mbus_frame *frame)
     if (_mbus_recv_event)
         _mbus_recv_event(MBUS_HANDLE_TYPE_TCP, buff, len);
       
-    if (remaining < 0)
+    if (remaining != 0)
     {
         mbus_error_str_set("M-Bus layer failed to parse data.");
         return -2;