diff --git a/include/mosquitto/broker.h b/include/mosquitto/broker.h
index 672db3ef..e5efb95c 100644
--- a/include/mosquitto/broker.h
+++ b/include/mosquitto/broker.h
@@ -616,6 +616,14 @@ mosq_EXPORT bool mosquitto_client_clean_session(const struct mosquitto *client);
 mosq_EXPORT const char *mosquitto_client_id(const struct mosquitto *client);
 
 
+/*
+ * Function: mosquitto_client_id_hashv
+ *
+ * Retrieve the hash value associated with a client id.
+ */
+mosq_EXPORT unsigned mosquitto_client_id_hashv(const struct mosquitto *client);
+
+
 /*
  * Function: mosquitto_client_keepalive
  *
diff --git a/lib/mosquitto_internal.h b/lib/mosquitto_internal.h
index 910c6dd5..64d20fb8 100644
--- a/lib/mosquitto_internal.h
+++ b/lib/mosquitto_internal.h
@@ -302,6 +302,7 @@ struct mosquitto {
 	char *id;
 	char *username;
 	char *password;
+	unsigned id_hashv;
 	uint16_t keepalive;
 	uint16_t last_mid;
 	enum mosquitto_client_state state;
diff --git a/src/context.c b/src/context.c
index ce1deccf..f2b2d7c9 100644
--- a/src/context.c
+++ b/src/context.c
@@ -329,7 +329,8 @@ void context__add_to_by_id(struct mosquitto *context)
 {
 	if(context->in_by_id == false){
 		context->in_by_id = true;
-		HASH_ADD_KEYPTR(hh_id, db.contexts_by_id, context->id, strlen(context->id), context);
+		HASH_VALUE(context->id, strlen(context->id), context->id_hashv);
+		HASH_ADD_KEYPTR_BYHASHVALUE(hh_id, db.contexts_by_id, context->id, strlen(context->id), context->id_hashv, context);
 	}
 }
 
@@ -348,6 +349,7 @@ void context__remove_from_by_id(struct mosquitto *context)
 		if(context_found){
 			HASH_DELETE(hh_id, db.contexts_by_id, context_found);
 		}
+		context->id_hashv = 0;
 		context->in_by_id = false;
 	}
 }
diff --git a/src/linker-macosx.syms b/src/linker-macosx.syms
index fea51df1..dbae1332 100644
--- a/src/linker-macosx.syms
+++ b/src/linker-macosx.syms
@@ -10,6 +10,7 @@ _mosquitto_client_address
 _mosquitto_client_certificate
 _mosquitto_client_clean_session
 _mosquitto_client_id
+_mosquitto_client_id_hashv
 _mosquitto_client_keepalive
 _mosquitto_client_port
 _mosquitto_client_protocol
diff --git a/src/linker.syms b/src/linker.syms
index 9867f369..e0823a88 100644
--- a/src/linker.syms
+++ b/src/linker.syms
@@ -11,6 +11,7 @@
 	mosquitto_client_certificate;
 	mosquitto_client_clean_session;
 	mosquitto_client_id;
+	mosquitto_client_id_hashv;
 	mosquitto_client_keepalive;
 	mosquitto_client_port;
 	mosquitto_client_protocol;
diff --git a/src/plugin_public.c b/src/plugin_public.c
index fe3054f9..2541d31d 100644
--- a/src/plugin_public.c
+++ b/src/plugin_public.c
@@ -104,6 +104,16 @@ BROKER_EXPORT const char *mosquitto_client_id(const struct mosquitto *client)
 }
 
 
+BROKER_EXPORT unsigned mosquitto_client_id_hashv(const struct mosquitto *client)
+{
+	if(client){
+		return client->id_hashv;
+	}else{
+		return 0;
+	}
+}
+
+
 BROKER_EXPORT int mosquitto_client_keepalive(const struct mosquitto *client)
 {
 	if(client){