diff --git a/pywb/warcserver/index/indexsource.py b/pywb/warcserver/index/indexsource.py
index 8305f3cc..c7b91d04 100644
--- a/pywb/warcserver/index/indexsource.py
+++ b/pywb/warcserver/index/indexsource.py
@@ -222,6 +222,8 @@ class RemoteIndexSource(BaseIndexSource):
 
 # =============================================================================
 class XmlQueryIndexSource(BaseIndexSource):
+    EXACT_QUERY = 'type:urlquery url:'
+    PREFIX_QUERY = 'type:prefixquery url:'
 
     def __init__(self, query_api_url):
         self.query_api_url = query_api_url
@@ -235,13 +237,16 @@ class XmlQueryIndexSource(BaseIndexSource):
         matchType = params.get('matchType', 'exact')
 
         if matchType == 'exact':
-            query_url = self.query_api_url + '?q=' + quote_plus('type:urlquery url:' + quote_plus(url))
+            query = self.EXACT_QUERY
         elif matchType == 'prefix':
-            query_url = self.query_api_url + '?q=' + quote_plus('type:prefixquery url:' + quote_plus(url))
+            query = self.PREFIX_QUERY
         else:
             raise BadRequestException('matchType={0} is not supported'.format(matchType=matchType))
 
         try:
+            #OpenSearch API requires double-escaping
+            #TODO: add option to not double escape if needed
+            query_url = self.query_api_url + '?q' + quote_plus(query + quote_plus(url))
             self.logger.debug("Running query: %s" % query_url)
             response = self.session.get(query_url)
             response.raise_for_status()
diff --git a/pywb/warcserver/index/test/test_xmlquery_indexsource.py b/pywb/warcserver/index/test/test_xmlquery_indexsource.py
index 22158148..3a3da4bb 100644
--- a/pywb/warcserver/index/test/test_xmlquery_indexsource.py
+++ b/pywb/warcserver/index/test/test_xmlquery_indexsource.py
@@ -10,14 +10,14 @@ import pytest
 # ============================================================================
 def mock_get(self, url):
     string = ''
-    if 'type:urlquery' in url:
-        if 'http%3A%2F%2Fexample.com%2Fsome%2Fpath' in url:
+    if 'type%3Aurlquery' in url:
+        if 'http%253A%252F%252Fexample.com%252Fsome%252Fpath' in url:
             string = URL_RESPONSE_2
 
-        elif 'http%3A%2F%2Fexample.com%2F' in url:
+        elif 'http%253A%252F%252Fexample.com%252F' in url:
             string = URL_RESPONSE_1
 
-    elif 'type:prefixquery' in url:
+    elif 'type%3Aprefixquery' in url:
         string = PREFIX_QUERY
 
     class MockResponse(object):