diff --git a/include/osmocom/gprs/gprs_bssgp_rim.h b/include/osmocom/gprs/gprs_bssgp_rim.h
index 7f3a0e4..7e9efcd 100644
--- a/include/osmocom/gprs/gprs_bssgp_rim.h
+++ b/include/osmocom/gprs/gprs_bssgp_rim.h
@@ -54,6 +54,10 @@
 	};
 };
 
+/* The encoded result of the rim routing information is, depending on the
+ * address type (discr) of variable length. */
+#define BSSGP_RIM_ROUTING_INFO_MAXLEN 14
+
 int bssgp_parse_rim_ri(struct bssgp_rim_routing_info *ri, const uint8_t *buf, unsigned int len);
 int bssgp_create_rim_ri(uint8_t *buf, const struct bssgp_rim_routing_info *ri);