diff --git a/iopipe/contrib/trace/plugin.py b/iopipe/contrib/trace/plugin.py
index bfb64e0f..6e225fdf 100644
--- a/iopipe/contrib/trace/plugin.py
+++ b/iopipe/contrib/trace/plugin.py
@@ -31,9 +31,11 @@ def __init__(
         :type http_headers: list|tuple
         """
         self.auto_measure = auto_measure
-        self.auto_http = auto_http is True or strtobool(
-            os.getenv("IOPIPE_TRACE_AUTO_HTTP_ENABLED", "false")
-        )
+        self.auto_http = auto_http
+        if "IOPIPE_TRACE_AUTO_HTTP_ENABLED" in os.environ:
+            self.auto_http = bool(
+                strtobool(os.environ["IOPIPE_TRACE_AUTO_HTTP_ENABLED"])
+            )
         self.http_filter = http_filter
         self.http_headers = http_headers
 
diff --git a/tests/contrib/trace/test_plugin.py b/tests/contrib/trace/test_plugin.py
index f005d9bd..6c5def37 100644
--- a/tests/contrib/trace/test_plugin.py
+++ b/tests/contrib/trace/test_plugin.py
@@ -1,5 +1,8 @@
 import mock
 
+from iopipe import IOpipeCore
+from iopipe.contrib.trace import TracePlugin
+
 
 @mock.patch("iopipe.report.send_report", autospec=True)
 def test__trace_plugin(mock_send_report, handler_with_trace, mock_context):
@@ -180,3 +183,11 @@ def test_trace_plugin__auto_http__filter_request(
     assert len(traces) == 1
     assert "request" not in traces[0]
     assert "response" in traces[0]
+
+
+def test__trace_plugin__auto_http__env_var(monkeypatch):
+    monkeypatch.setenv("IOPIPE_TRACE_AUTO_HTTP_ENABLED", "false")
+
+    iopipe = IOpipeCore(plugins=[TracePlugin()])
+
+    assert iopipe.plugins[0].auto_http is False