--- sys/netpfil/pf/pf.c
+++ sys/netpfil/pf/pf.c
@@ -6001,7 +6001,7 @@
 	    pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
 	    (s->nat_rule.ptr->action == PF_RDR ||
 	    s->nat_rule.ptr->action == PF_BINAT) &&
-	    (ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
+	    IN_LOOPBACK(ntohl(pd.dst->v4.s_addr)))
 		m->m_flags |= M_SKIP_FIREWALL;
 
 	if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&