diff --git a/lib/packets.h b/lib/packets.h
index a9d5e844e..8c9c741fa 100644
--- a/lib/packets.h
+++ b/lib/packets.h
@@ -126,10 +126,18 @@ pkt_metadata_init_tnl(struct pkt_metadata *md)
 static inline void
 pkt_metadata_init(struct pkt_metadata *md, odp_port_t port)
 {
+    /* This is called for every packet in userspace datapath and affects
+     * performance if all the metadata is initialized. Hence, fields should
+     * only be zeroed out when necessary.
+     *
+     * Initialize only till ct_state. Once the ct_state is zeroed out rest
+     * of ct fields will not be looked at unless ct_state != 0.
+     */
+    memset(md, 0, offsetof(struct pkt_metadata, ct_orig_tuple_ipv6));
+
     /* It can be expensive to zero out all of the tunnel metadata. However,
      * we can just zero out ip_dst and the rest of the data will never be
      * looked at. */
-    memset(md, 0, offsetof(struct pkt_metadata, in_port));
     md->tunnel.ip_dst = 0;
     md->tunnel.ipv6_dst = in6addr_any;
     md->in_port.odp_port = port;