diff --git a/src/main/scala/chisel3/Driver.scala b/src/main/scala/chisel3/Driver.scala
index 9876c495692..2006a6c79b1 100644
--- a/src/main/scala/chisel3/Driver.scala
+++ b/src/main/scala/chisel3/Driver.scala
@@ -134,7 +134,7 @@ object Driver extends BackendCompilationUtilities {
     * @param optName An optional filename (will use s"${ir.name}.json" otherwise)
     */
   def dumpAnnotations(ir: Circuit, optName: Option[File]): File = {
-    val f = optName.getOrElse(new File(ir.name + ".json"))
+    val f = optName.getOrElse(new File(ir.name + ".anno.json"))
     val w = new FileWriter(f)
     w.write(JsonProtocol.serialize(ir.annotations.map(_.toFirrtl)))
     w.close()