diff --git a/src/plugins/elasticsearch/lib/__tests__/call_with_request.js b/src/plugins/elasticsearch/lib/__tests__/call_with_request.js
new file mode 100644
index 0000000000000..ac487e91bce0c
--- /dev/null
+++ b/src/plugins/elasticsearch/lib/__tests__/call_with_request.js
@@ -0,0 +1,28 @@
+import expect from 'expect.js';
+import callWithRequest from '../call_with_request';
+
+describe('call_with_request', () => {
+  let mockClient;
+
+  beforeEach(() => {
+    mockClient = {
+      search(params) {
+        this.params = params;
+        return Promise.resolve(this);
+      }
+    };
+  });
+
+  it ('passes through all headers', () => {
+    const mockRequest = {
+      headers: {
+        authorization: 'Basic QWxhZGRpbjpPcGVuU2VzYW1l',
+        'kbn-version': '4.6.0'
+      }
+    };
+    return callWithRequest(mockClient)(mockRequest, 'search')
+    .then(() => {
+      expect(mockClient.params.headers).to.be(mockRequest.headers);
+    });
+  });
+});
diff --git a/src/plugins/elasticsearch/lib/call_with_request.js b/src/plugins/elasticsearch/lib/call_with_request.js
index cf440b260219a..a2026a86edf83 100644
--- a/src/plugins/elasticsearch/lib/call_with_request.js
+++ b/src/plugins/elasticsearch/lib/call_with_request.js
@@ -6,9 +6,7 @@ const toPath = require('lodash/internal/toPath');
 
 module.exports = (client) => {
   return (req, endpoint, params = {}) => {
-    if (req.headers.authorization) {
-      _.set(params, 'headers.authorization', req.headers.authorization);
-    }
+    _.set(params, 'headers', req.headers);
     const path = toPath(endpoint);
     const api = _.get(client, path);
     let apiContext = _.get(client, path.slice(0, -1));