diff --git a/cores/esp8266/cbuf.cpp b/cores/esp8266/cbuf.cpp
index ca5977df48..e655ca6fc6 100644
--- a/cores/esp8266/cbuf.cpp
+++ b/cores/esp8266/cbuf.cpp
@@ -39,7 +39,7 @@ size_t cbuf::resize(size_t newSize) {
 
 	// not lose any data
 	// if data can be lost use remove or flush before resize
-    if((newSize < bytes_available) || (newSize == _size)) {
+    if((newSize <= bytes_available) || (newSize == _size)) {
         return _size;
     }