diff --git a/packages/blockstore-s3/package.json b/packages/blockstore-s3/package.json
index ef8d49c3..c99856e8 100644
--- a/packages/blockstore-s3/package.json
+++ b/packages/blockstore-s3/package.json
@@ -157,6 +157,6 @@
     "aegir": "^47.0.16",
     "interface-blockstore-tests": "^7.0.0",
     "p-defer": "^4.0.1",
-    "sinon": "^20.0.0"
+    "sinon": "^21.0.0"
   }
 }
diff --git a/packages/datastore-s3/package.json b/packages/datastore-s3/package.json
index 0498fd24..5f9e12e4 100644
--- a/packages/datastore-s3/package.json
+++ b/packages/datastore-s3/package.json
@@ -157,6 +157,6 @@
     "aegir": "^47.0.16",
     "interface-datastore-tests": "^6.0.0",
     "p-defer": "^4.0.1",
-    "sinon": "^20.0.0"
+    "sinon": "^21.0.0"
   }
 }