diff --git a/source/thread_shared.c b/source/thread_shared.c
index a0d19adfe..cbceb428e 100644
--- a/source/thread_shared.c
+++ b/source/thread_shared.c
@@ -40,8 +40,8 @@ void aws_thread_increment_unjoined_count(void) {
 void aws_thread_decrement_unjoined_count(void) {
     aws_mutex_lock(&s_managed_thread_lock);
     --s_unjoined_thread_count;
-    aws_mutex_unlock(&s_managed_thread_lock);
     aws_condition_variable_notify_one(&s_managed_thread_signal);
+    aws_mutex_unlock(&s_managed_thread_lock);
 }
 
 size_t aws_thread_get_managed_thread_count(void) {