diff --git a/package.json b/package.json
index 93fb780f..a43dd5c9 100644
--- a/package.json
+++ b/package.json
@@ -90,7 +90,7 @@
     "@types/arrify": "^1.0.4",
     "@types/big.js": "^4.0.5",
     "@types/extend": "^3.0.0",
-    "@types/is": "0.0.20",
+    "@types/is": "0.0.21",
     "@types/mocha": "^5.2.5",
     "@types/proxyquire": "^1.3.28",
     "@types/request": "^2.48.0",