diff --git a/lib/mixins/template-stamp.js b/lib/mixins/template-stamp.js
index 4e4023c06..19938efe0 100644
--- a/lib/mixins/template-stamp.js
+++ b/lib/mixins/template-stamp.js
@@ -301,7 +301,7 @@ export const TemplateStamp = dedupingMixin(
         templateInfo.nestedTemplate = Boolean(outerTemplateInfo);
         templateInfo.stripWhiteSpace =
           (outerTemplateInfo && outerTemplateInfo.stripWhiteSpace) ||
-          template.hasAttribute('strip-whitespace');
+          (template.hasAttribute && template.hasAttribute('strip-whitespace'));
          // TODO(rictic): fix typing
          this._parseTemplateContent(
              template, templateInfo, /** @type {?} */ ({parent: null}));