diff --git a/CHANGELOG.md b/CHANGELOG.md
index a0f927324c..010bca804f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 1.12.20
+
+ * Append `sourceMappingURL` when using `bin/6to5` and output sourcemaps.
+
 # 1.12.19
 
  * Add `comments` option and `--remove-comments` flag. Thanks @[webpro](htps://github.com/webpro)!
diff --git a/bin/6to5/dir.js b/bin/6to5/dir.js
index 9854f33472..376d0bf571 100644
--- a/bin/6to5/dir.js
+++ b/bin/6to5/dir.js
@@ -19,7 +19,9 @@ module.exports = function (commander, filenames, opts) {
     mkdirp.sync(up);
 
     if (commander.sourceMaps) {
-      fs.writeFileSync(dest + ".map", JSON.stringify(data.map));
+      var mapLoc = dest + ".map";
+      data.code = util.addSourceMappingUrl(data.code, mapLoc);
+      fs.writeFileSync(mapLoc, JSON.stringify(data.map));
     }
 
     fs.writeFileSync(dest, data.code);
diff --git a/bin/6to5/file.js b/bin/6to5/file.js
index 82112f8cfb..73c0f19a7f 100644
--- a/bin/6to5/file.js
+++ b/bin/6to5/file.js
@@ -56,7 +56,9 @@ module.exports = function (commander, filenames) {
 
     if (commander.outFile) {
       if (commander.sourceMaps) {
-        fs.writeFileSync(commander.outFile + ".map", JSON.stringify(result.map));
+        var mapLoc = commander.outFile + ".map";
+        result.code = util.addSourceMappingUrl(result.code, mapLoc);
+        fs.writeFileSync(mapLoc, JSON.stringify(result.map));
       }
 
       fs.writeFileSync(commander.outFile, result.code);
diff --git a/bin/6to5/util.js b/bin/6to5/util.js
index c94c09090b..1adf6d5119 100644
--- a/bin/6to5/util.js
+++ b/bin/6to5/util.js
@@ -1,6 +1,7 @@
 var readdir = require("fs-readdir-recursive");
 var index   = require("./index");
 var util    = require("../../lib/6to5/util");
+var path    = require("path");
 var to5     = require("../../lib/6to5");
 var fs      = require("fs");
 var _       = require("lodash");
@@ -11,6 +12,10 @@ exports.readdirFilter = function (filename) {
   });
 };
 
+exports.addSourceMappingUrl = function (code, loc) {
+  return code + "\n//# sourceMappingURL=" + path.basename(loc);
+};
+
 exports.transform = function (filename, code, opts) {
   opts = _.extend(opts || {}, index.opts);
   opts.filename = filename;
diff --git a/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/bar/bar.js b/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/bar/bar.js
index 5f98760f68..549259d579 100644
--- a/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/bar/bar.js	
+++ b/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/bar/bar.js	
@@ -1,3 +1,4 @@
 "use strict";
 
 var Test = function Test() {};
+//# sourceMappingURL=bar.js.map
diff --git a/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/foo.js b/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/foo.js
index ae4557e57b..7a5ff48137 100644
--- a/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/foo.js	
+++ b/test/fixtures/bin/6to5/dir --out-dir --source-maps/out-files/lib/foo.js	
@@ -3,3 +3,4 @@
 arr.map(function (x) {
   return x * MULTIPLIER;
 });
+//# sourceMappingURL=foo.js.map
diff --git a/test/fixtures/bin/6to5/filenames --out-file --source-maps/out-files/script3.js b/test/fixtures/bin/6to5/filenames --out-file --source-maps/out-files/script3.js
index 7421f83f81..695ecc125b 100644
--- a/test/fixtures/bin/6to5/filenames --out-file --source-maps/out-files/script3.js	
+++ b/test/fixtures/bin/6to5/filenames --out-file --source-maps/out-files/script3.js	
@@ -6,3 +6,5 @@ var Test = function Test() {};
 arr.map(function (x) {
   return x * MULTIPLIER;
 });
+
+//# sourceMappingURL=script3.js.map
diff --git a/test/fixtures/bin/6to5/stdin --out-file --source-maps/out-files/test.js b/test/fixtures/bin/6to5/stdin --out-file --source-maps/out-files/test.js
index e136af8d90..303fade7a2 100644
--- a/test/fixtures/bin/6to5/stdin --out-file --source-maps/out-files/test.js	
+++ b/test/fixtures/bin/6to5/stdin --out-file --source-maps/out-files/test.js	
@@ -3,3 +3,5 @@
 arr.map(function (x) {
   return x * x;
 });
+
+//# sourceMappingURL=test.js.map