diff --git a/stress-http.js b/stress-http.js
index fa804b78aef96b9f718983dad42a1f7527f309f7..441d916a9af072a52c7b21f8ed2932fddc4c1a20 100644
--- a/stress-http.js
+++ b/stress-http.js
@@ -408,6 +408,8 @@ new Promise( resolve => {
 			}
 
 			function cancelClient( client ) {
+				clearInterval( client.statsTimer );
+
 				cancelled[client.id] = true;
 
 				if ( Object.keys( cancelled ).length >= NumClients ) {