diff --git a/src/nvim/os/win_defs.h b/src/nvim/os/win_defs.h
index 242d355f77..55894e4d12 100644
--- a/src/nvim/os/win_defs.h
+++ b/src/nvim/os/win_defs.h
@@ -1,6 +1,9 @@
 #ifndef NVIM_OS_WIN_DEFS_H
 #define NVIM_OS_WIN_DEFS_H
 
+// winsock2.h must be first to avoid incompatibilities
+// with winsock.h (included by windows.h)
+#include <winsock2.h>
 #include <windows.h>
 #include <sys/stat.h>
 #include <io.h>