diff --git a/rules/src/main/scala/fix/DirectoryAndPackageName.scala b/rules/src/main/scala/fix/DirectoryAndPackageName.scala
index 11981e3..70b6c62 100644
--- a/rules/src/main/scala/fix/DirectoryAndPackageName.scala
+++ b/rules/src/main/scala/fix/DirectoryAndPackageName.scala
@@ -10,6 +10,7 @@ import scalafix.v1.Configuration
 import scalafix.v1.Rule
 import scalafix.v1.SyntacticDocument
 import scalafix.v1.SyntacticRule
+import java.io.File
 import java.util.Locale
 import scala.meta.Pkg
 import scala.meta.Term
@@ -133,18 +134,25 @@ class DirectoryAndPackageName(config: DirectoryAndPackageNameConfig) extends Syn
         x
       }.headOption
 
-    val scalaSourceOpt = PartialFunction.condOpt(doc.input) {
-      case f: Input.VirtualFile =>
-        f.path
-      case f: Input.File =>
-        f.path.toString
-    }
+    val scalaSourceOpt = PartialFunction
+      .condOpt(doc.input) {
+        case f: Input.VirtualFile =>
+          f.path
+        case f: Input.File =>
+          f.path.toString
+      }
+      .map { path =>
+        File.separatorChar match {
+          case '/' =>
+            path
+          case c =>
+            path.replace(c, '/')
+        }
+      }
 
     {
       for {
         path <- scalaSourceOpt
-        // TODO Windows
-        if !scala.util.Properties.isWin
         dirOpt = config.baseDirectory.find { dir =>
           path.contains(dir)
         }.map { dir =>