diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite.c b/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite.c
index 06071c4..5984d96 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite.c
@@ -27,6 +27,7 @@
 #include <openbsc/gsm_data.h>
 #include <openbsc/debug.h>
 #include <openbsc/ipaccess.h>
+#include <openbsc/nat_rewrite_trie.h>
 
 #include <osmocom/core/linuxlist.h>
 #include <osmocom/core/talloc.h>
@@ -37,9 +38,30 @@
 
 #include <osmocom/sccp/sccp.h>
 
+static char *trie_lookup(struct nat_rewrite *trie, const char *number,
+			regoff_t off, void *ctx)
+{
+	struct nat_rewrite_rule *rule;
+
+	if (!trie) {
+		LOGP(DNAT, LOGL_ERROR,
+			"Asked to do a table lookup but no table.\n");
+		return NULL;
+	}
+
+	rule = nat_rewrite_lookup(trie, number);
+	if (!rule) {
+		LOGP(DNAT, LOGL_DEBUG,
+			"Couldn't find a prefix rule for %s\n", number);
+		return NULL;
+	}
+
+	return talloc_asprintf(ctx, "%s%s", rule->rewrite, &number[off]);
+}
+
 static char *match_and_rewrite_number(void *ctx, const char *number,
-				      const char *imsi,
-				      struct llist_head *list)
+				const char *imsi, struct llist_head *list,
+				struct nat_rewrite *trie)
 {
 	struct bsc_nat_num_rewr_entry *entry;
 	char *new_number = NULL;
@@ -53,11 +75,17 @@
 			continue;
 
 		/* this regexp matches... */
-		if (regexec(&entry->num_reg, number, 2, matches, 0) == 0 &&
-		    matches[1].rm_eo != -1)
-			new_number = talloc_asprintf(ctx, "%s%s",
+		if (regexec(&entry->num_reg, number, 2, matches, 0) == 0
+			&& matches[1].rm_eo != -1) {
+			if (entry->is_prefix_lookup)
+				new_number = trie_lookup(trie, number,
+						matches[1].rm_so, ctx);
+			else
+				new_number = talloc_asprintf(ctx, "%s%s",
 					entry->replace,
 					&number[matches[1].rm_so]);
+		}
+
 		if (new_number)
 			break;
 	}
@@ -86,7 +114,7 @@
 	}
 
 	return match_and_rewrite_number(ctx, number,
-					imsi, &nat->num_rewr);
+					imsi, &nat->num_rewr, nat->num_rewr_trie);
 }
 
 
@@ -261,7 +289,7 @@
 			     const char *imsi, const char *dest_nr)
 {
 	return match_and_rewrite_number(ctx, dest_nr, imsi,
-					&nat->sms_num_rewr);
+					&nat->sms_num_rewr, NULL);
 }
 
 /**
@@ -600,6 +628,9 @@
 			continue;
 		}
 
+		if (strcmp("prefix_lookup", entry->replace) == 0)
+			entry->is_prefix_lookup = 1;
+
 		/* we will now build a regexp string */
 		if (cfg_entry->mcc[0] == '^') {
 			regexp = talloc_strdup(entry, cfg_entry->mcc);
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c b/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c
index 57043ac..faceb59 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_rewrite_trie.c
@@ -21,6 +21,7 @@
 
 #include <openbsc/nat_rewrite_trie.h>
 #include <openbsc/debug.h>
+#include <openbsc/vty.h>
 
 #include <osmocom/core/talloc.h>
 #include <osmocom/core/utils.h>
@@ -238,3 +239,21 @@
 {
 	nat_rewrite_dump_rec(&rewrite->rule);
 }
+
+static void nat_rewrite_dump_rec_vty(struct vty *vty, struct nat_rewrite_rule *rule)
+{
+	int i;
+	if (!rule->empty)
+		vty_out(vty, "%s,%s%s", rule->prefix, rule->rewrite, VTY_NEWLINE);
+
+	for (i = 0; i < ARRAY_SIZE(rule->rules); ++i) {
+		if (!rule->rules[i])
+			continue;
+		nat_rewrite_dump_rec_vty(vty, rule->rules[i]);
+	}
+}
+
+void nat_rewrite_dump_vty(struct vty *vty, struct nat_rewrite *rewrite)
+{
+	nat_rewrite_dump_rec_vty(vty, &rewrite->rule);
+}
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c b/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
index 6774a42..5404bfb 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
@@ -26,6 +26,7 @@
 #include <openbsc/gsm_04_08.h>
 #include <openbsc/mgcp.h>
 #include <openbsc/vty.h>
+#include <openbsc/nat_rewrite_trie.h>
 
 #include <osmocom/core/talloc.h>
 #include <osmocom/core/rate_ctr.h>
@@ -138,6 +139,9 @@
 	if (_nat->sms_num_rewr_name)
 		vty_out(vty, " sms-number-rewrite %s%s",
 			_nat->sms_num_rewr_name, VTY_NEWLINE);
+	if (_nat->num_rewr_trie_name)
+		vty_out(vty, " prefix-tree %s%s",
+			_nat->num_rewr_trie_name, VTY_NEWLINE);
 
 	llist_for_each_entry(lst, &_nat->access_lists, list)
 		write_acc_lst(vty, lst);
@@ -633,6 +637,59 @@
 	return CMD_SUCCESS;
 }
 
+DEFUN(cfg_nat_prefix_trie,
+      cfg_nat_prefix_trie_cmd,
+      "prefix-tree FILENAME",
+      "Prefix tree for number rewriting\n" "File to load\n")
+{
+	/* give up the old data */
+	talloc_free(_nat->num_rewr_trie);
+	_nat->num_rewr_trie = NULL;
+
+	/* replace the file name */
+	bsc_replace_string(_nat, &_nat->num_rewr_trie_name, argv[0]);
+	if (!_nat->num_rewr_trie_name) {
+		vty_out(vty, "%% prefix-tree no filename is present.%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	_nat->num_rewr_trie = nat_rewrite_parse(_nat, _nat->num_rewr_trie_name);
+	if (!_nat->num_rewr_trie) {
+		vty_out(vty, "%% prefix-tree parsing has failed.%s", VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	vty_out(vty, "%% prefix-tree loaded %zu rules.%s",
+		_nat->num_rewr_trie->prefixes, VTY_NEWLINE);
+	return CMD_SUCCESS;
+}
+
+DEFUN(cfg_nat_no_prefix_trie, cfg_nat_no_prefix_trie_cmd,
+      "no prefix-tree",
+      NO_STR "Prefix tree for number rewriting\n")
+{
+	talloc_free(_nat->num_rewr_trie);
+	_nat->num_rewr_trie = NULL;
+	talloc_free(_nat->num_rewr_trie_name);
+	_nat->num_rewr_trie_name = NULL;
+
+	return CMD_SUCCESS;
+}
+
+DEFUN(show_prefix_tree, show_prefix_tree_cmd,
+      "show prefix-tree",
+      SHOW_STR "Prefix tree for number rewriting\n")
+{
+	if (!_nat->num_rewr_trie) {
+		vty_out(vty, "%% there is now prefix tree loaded.%s",
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	nat_rewrite_dump_vty(vty, _nat->num_rewr_trie);
+	return CMD_SUCCESS;
+}
+
 DEFUN(cfg_nat_ussd_lst_name,
       cfg_nat_ussd_lst_name_cmd,
       "ussd-list-name NAME",
@@ -1089,6 +1146,7 @@
 	install_element_ve(&show_bsc_mgcp_cmd);
 	install_element_ve(&show_acc_lst_cmd);
 	install_element_ve(&show_bar_lst_cmd);
+	install_element_ve(&show_prefix_tree_cmd);
 
 	install_element(ENABLE_NODE, &set_last_endp_cmd);
 	install_element(ENABLE_NODE, &block_new_conn_cmd);
@@ -1131,6 +1189,8 @@
 	install_element(NAT_NODE, &cfg_nat_no_sms_clear_tpsrr_cmd);
 	install_element(NAT_NODE, &cfg_nat_sms_number_rewrite_cmd);
 	install_element(NAT_NODE, &cfg_nat_no_sms_number_rewrite_cmd);
+	install_element(NAT_NODE, &cfg_nat_prefix_trie_cmd);
+	install_element(NAT_NODE, &cfg_nat_no_prefix_trie_cmd);
 
 	install_element(NAT_NODE, &cfg_nat_pgroup_cmd);
 	install_element(NAT_NODE, &cfg_nat_no_pgroup_cmd);