diff --git a/examples/gnrc_border_router/Makefile.native.conf b/examples/gnrc_border_router/Makefile.native.conf
index 47785a3447..3be2b8774b 100644
--- a/examples/gnrc_border_router/Makefile.native.conf
+++ b/examples/gnrc_border_router/Makefile.native.conf
@@ -5,6 +5,7 @@ ZEP_PORT_MAX := $(shell expr $(ZEP_PORT_BASE) + $(ZEP_DEVICES) - 1)
 
 CFLAGS += -DSOCKET_ZEP_MAX=$(ZEP_DEVICES)
 CFLAGS += -DASYNC_READ_NUMOF=$(shell expr $(ZEP_DEVICES) + 1)
+CFLAGS += -DCONFIG_DHCPV6_CLIENT_PFX_LEASE_MAX=$(ZEP_DEVICES)
 
 # Set CFLAGS if not being set via Kconfig
 CFLAGS += $(if $(CONFIG_KCONFIG_MODULE_DHCPV6),,-DCONFIG_DHCPV6_CLIENT_PFX_LEASE_MAX=$(ZEP_DEVICES))