diff --git a/boards/fox/Makefile.include b/boards/fox/Makefile.include
index 727bd481c6..d7955baeaa 100644
--- a/boards/fox/Makefile.include
+++ b/boards/fox/Makefile.include
@@ -4,7 +4,7 @@ export CPU_MODEL = stm32f103re
 
 # set default port depending on operating system
 PORT_LINUX ?= /dev/ttyUSB1
-PORT_DARWIN ?= $(firstword $(sort $(wildcard /dev/tty.usbserial*)))
+PORT_DARWIN ?= $(firstword $(sort $(wildcard /dev/tty.usbserial*B)))
 
 # setup serial terminal
 include $(RIOTBOARD)/Makefile.include.serial