diff --git a/sys/net/if_vlan_var.h b/sys/net/if_vlan_var.h
--- a/sys/net/if_vlan_var.h
+++ b/sys/net/if_vlan_var.h
@@ -131,7 +131,7 @@
 #define	DOT1Q_VID_DEF_SR_PVID	0x2
 #define	DOT1Q_VID_RSVD_IMPL	0xfff
 #define	DOT1Q_VID_MIN		1	/* minimum valid vlan id */
-#define	DOT1Q_VID_MAX		4095	/* maximum valid vlan id */
+#define	DOT1Q_VID_MAX		4094	/* maximum valid vlan id */
 
 /*
  * 802.1q full tag. Proto and vid are stored in host byte order.