diff --git a/lib/searchkick/query.rb b/lib/searchkick/query.rb
index bce1664..7695532 100644
--- a/lib/searchkick/query.rb
+++ b/lib/searchkick/query.rb
@@ -561,7 +561,9 @@ module Searchkick
 
     def custom_filter(field, value, factor)
       {
-        filter: term_filters(field, value),
+        filter: {
+          and: where_filters({field => value})
+        },
         boost_factor: factor
       }
     end
diff --git a/test/boost_test.rb b/test/boost_test.rb
index d726e7a..ae14d30 100644
--- a/test/boost_test.rb
+++ b/test/boost_test.rb
@@ -108,6 +108,7 @@ class TestBoost < Minitest::Test
       {name: "Tomato C", user_ids: [3]}
     ]
     assert_first "tomato", "Tomato B", boost_where: {user_ids: 2}
+    assert_first "tomato", "Tomato B", boost_where: {user_ids: 1..2}
     assert_first "tomato", "Tomato B", boost_where: {user_ids: [1, 4]}
     assert_first "tomato", "Tomato B", boost_where: {user_ids: {value: 2, factor: 10}}
     assert_first "tomato", "Tomato B", boost_where: {user_ids: {value: [1, 4], factor: 10}}
--
libgit2 0.21.0