diff --git a/socket.c b/socket.c
index 4879123..65befc7 100644
--- a/socket.c
+++ b/socket.c
@@ -1020,8 +1020,6 @@ send_message(int sock_fd, SCK_Message *message, int flags)
         return 0;
 
       ipi->ipi_spec_dst.s_addr = htonl(message->local_addr.ip.addr.in4);
-      if (message->if_index != INVALID_IF_INDEX)
-        ipi->ipi_ifindex = message->if_index;
 
 #elif defined(IP_SENDSRCADDR)
       struct in_addr *addr;
@@ -1046,8 +1044,6 @@ send_message(int sock_fd, SCK_Message *message, int flags)
 
       memcpy(&ipi->ipi6_addr.s6_addr, &message->local_addr.ip.addr.in6,
              sizeof(ipi->ipi6_addr.s6_addr));
-      if (message->if_index != INVALID_IF_INDEX)
-        ipi->ipi6_ifindex = message->if_index;
     }
 #endif
   }