diff --git a/tools/wptrunner/wptrunner/executors/executorservo.py b/tools/wptrunner/wptrunner/executors/executorservo.py
index 89aaf00352f4142..125670633ccdd33 100644
--- a/tools/wptrunner/wptrunner/executors/executorservo.py
+++ b/tools/wptrunner/wptrunner/executors/executorservo.py
@@ -38,6 +38,7 @@ def build_servo_command(test, test_url_func, browser, binary, pause_after_test,
                         extra_args=None, debug_opts="replace-surrogates"):
     args = [
         "--hard-fail", "-u", "Servo/wptrunner",
+        "--ignore-certificate-errors",
         "-z", test_url_func(test),
     ]
     if debug_opts: