diff --git a/webhook/views.py b/webhook/views.py
index 842f55b5..84e53724 100644
--- a/webhook/views.py
+++ b/webhook/views.py
@@ -17,10 +17,15 @@ logger = logging.getLogger(__name__)
 @csrf_exempt
 def handle_invoice_webhook(request):
     payload = request.body
-    sig_header = request.META['HTTP_STRIPE_SIGNATURE']
     event = None
 
     try:
+        if 'HTTP_STRIPE_SIGNATURE' in request.META:
+            sig_header = request.META['HTTP_STRIPE_SIGNATURE']
+        else:
+            logger.error("No HTTP_STRIPE_SIGNATURE header")
+            # Invalid payload
+            return HttpResponse(status=400)
         event = stripe.Webhook.construct_event(
             payload, sig_header, settings.INVOICE_WEBHOOK_SECRET
         )