diff --git a/lib/less/source-map-output.js b/lib/less/source-map-output.js
index a86c7ec6..b8bd45e2 100644
--- a/lib/less/source-map-output.js
+++ b/lib/less/source-map-output.js
@@ -39,8 +39,11 @@
     tree.sourceMapOutput.prototype.toCSS = function(env) {
         this._sourceMapGenerator = new sourceMap.SourceMapGenerator({ file:"outputFilenameTODO.css", sourceRoot:"http://blah.com/TODO" });
 
-        for(var filename in this._contentsMap) {
-            this._sourceMapGenerator.setSourceContent(filename, this._contentsMap[filename]);
+        //TODO option to include source in sourcemaps?
+        if (this._outputSourceFiles) {
+            for(var filename in this._contentsMap) {
+                this._sourceMapGenerator.setSourceContent(filename, this._contentsMap[filename]);
+            }
         }
 
         this._rootNode.genCSS(env, this);
diff --git a/test/sourcemaps/basic.json b/test/sourcemaps/basic.json
index 7191a765..415d3e5a 100644
--- a/test/sourcemaps/basic.json
+++ b/test/sourcemaps/basic.json
@@ -1 +1 @@
-// ha
\ No newline at end of file
+{"version":3,"file":"basic.css","sources":["basic.less"],"names":[],"mappings":"EAIE,UAAA;aAJA,QAAA;sBAMA,SAAA","sourceRoot":""}
\ No newline at end of file