diff --git a/lib/ns/xfrout.c b/lib/ns/xfrout.c
index 9380924bf6..1429d3be6b 100644
--- a/lib/ns/xfrout.c
+++ b/lib/ns/xfrout.c
@@ -1264,7 +1264,7 @@ xfrout_ctx_create(isc_mem_t *mctx, ns_client_t *client, unsigned int id,
 	 * Note that although 65535-byte RRs are allowed in principle, they
 	 * cannot be zone-transferred (at least not if uncompressible),
 	 * because the message and RR headers would push the size of the
-	 * TCP message over the 65536 byte limit.
+	 * TCP message over the 65535 byte limit.
 	 */
 	mem = isc_mem_get(mctx, len);
 	isc_buffer_init(&xfr->buf, mem, len);