diff --git a/wagtail/tests/context_processors.py b/wagtail/tests/context_processors.py
new file mode 100644
index 0000000000..63d0ab683c
--- /dev/null
+++ b/wagtail/tests/context_processors.py
@@ -0,0 +1,7 @@
+def do_not_use_static_url(request):
+    def exception():
+        raise Exception("Do not use STATIC_URL in templates. Use the {% static %} templatetag instead.")
+
+    return {
+        'STATIC_URL': lambda: exception(),
+    }
diff --git a/wagtail/tests/settings.py b/wagtail/tests/settings.py
index a03b9d8873..6bbe14e561 100644
--- a/wagtail/tests/settings.py
+++ b/wagtail/tests/settings.py
@@ -48,6 +48,7 @@ if django.VERSION >= (1, 8):
                     'django.contrib.auth.context_processors.auth',
                     'django.contrib.messages.context_processors.messages',
                     'django.template.context_processors.request',
+                    'wagtail.tests.context_processors.do_not_use_static_url',
                 ],
             },
         },
@@ -55,6 +56,7 @@ if django.VERSION >= (1, 8):
 else:
     TEMPLATE_CONTEXT_PROCESSORS = global_settings.TEMPLATE_CONTEXT_PROCESSORS + (
         'django.core.context_processors.request',
+        'wagtail.tests.context_processors.do_not_use_static_url',
     )
 
 MIDDLEWARE_CLASSES = (