diff --git a/net/tcp/tcp_conn.c b/net/tcp/tcp_conn.c
index 0fadc202d02..7ed6e34494e 100644
--- a/net/tcp/tcp_conn.c
+++ b/net/tcp/tcp_conn.c
@@ -535,6 +535,7 @@ int tcp_selectport(uint8_t domain,
             {
               /* We have looped back, failed. */
 
+              tcp_conn_list_unlock();
               return -EADDRINUSE;
             }
         }
@@ -558,6 +559,7 @@ int tcp_selectport(uint8_t domain,
         {
           /* It is in use... return EADDRINUSE */
 
+          tcp_conn_list_unlock();
           return -EADDRINUSE;
         }
     }