diff --git a/src/formatting/xml-formatter.ts b/src/formatting/xml-formatter.ts
index ddfa361..01fb9ae 100644
--- a/src/formatting/xml-formatter.ts
+++ b/src/formatting/xml-formatter.ts
@@ -1,6 +1,6 @@
-import { workspace } from "vscode";
+import { window, workspace } from "vscode";
 
-import { Configuration } from "../common";
+import { Configuration, ExtensionState } from "../common";
 import * as constants from "../constants";
 import { ClassicXmlFormatter } from "./formatters/classic-xml-formatter";
 import { V2XmlFormatter } from "./formatters/v2-xml-formatter";
@@ -29,6 +29,17 @@ export class XmlFormatterFactory {
             default: xmlFormatterImplementation = new V2XmlFormatter(); break;
         }
 
+        // warn users about the new formatter
+        const formatterWarningKey = "xmlTools.v2FormatterWarning.shown";
+
+        if (!ExtensionState.global.get<boolean>(formatterWarningKey) && xmlFormatterImplementation instanceof V2XmlFormatter) {
+            // tslint:disable-next-line:max-line-length
+            window.showInformationMessage("Heads up! We've rewritten the XML formatter. If you liked the old one better, it's still there. Just set the 'xmlTools.xmlFormatterImplementation' setting to 'classic'.")
+                .then(() => {
+                    ExtensionState.global.update(formatterWarningKey, true);
+                });
+        }
+
         return (XmlFormatterFactory._xmlFormatter = xmlFormatterImplementation);
     }
 }