diff --git a/lib/http-api.js b/lib/http-api.js
index 1f4d42a43..f8a72978b 100644
--- a/lib/http-api.js
+++ b/lib/http-api.js
@@ -395,7 +395,7 @@ module.exports.MatrixHttpApi.prototype = {
                 timedOut = true;
                 defer.reject(new module.exports.MatrixError({
                     error: "Locally timed out waiting for a response",
-                    errcode: "ORG_MATRIX_JSSDK_TIMEOUT",
+                    errcode: "ORG.MATRIX.JSSDK_TIMEOUT",
                     timeout: localTimeoutMs
                 }));
             }, localTimeoutMs);