diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -855,7 +855,7 @@
 	}
 
 	if (ifa->ifa_addr->sa_family == AF_INET) {
-		multicast = IN_MULTICAST(sc->sc_carpaddr.s_addr);
+		multicast = IN_MULTICAST(ntohl(sc->sc_carpaddr.s_addr));
 	} else {
 		multicast = IN6_IS_ADDR_MULTICAST(&sc->sc_carpaddr6);
 	}
@@ -1245,7 +1245,7 @@
 		m->m_pkthdr.rcvif = NULL;
 		m->m_len = len;
 		M_ALIGN(m, m->m_len);
-		if (IN_MULTICAST(sc->sc_carpaddr.s_addr))
+		if (IN_MULTICAST(ntohl(sc->sc_carpaddr.s_addr)))
 			m->m_flags |= M_MCAST;
 		ip = mtod(m, struct ip *);
 		ip->ip_v = IPVERSION;