diff --git a/lib/vagrant/pre-rubygems.rb b/lib/vagrant/pre-rubygems.rb
index 451fdd263..5ea8a28e6 100644
--- a/lib/vagrant/pre-rubygems.rb
+++ b/lib/vagrant/pre-rubygems.rb
@@ -21,4 +21,12 @@ plugins = Vagrant::Plugin::Manager.instance.installed_plugins
 Vagrant::Bundler.instance.init!(plugins)
 
 ENV["VAGRANT_INTERNAL_BUNDLERIZED"] = "1"
-Kernel.exec("vagrant", *ARGV)
+
+# If the VAGRANT_EXECUTABLE env is set, then we use that to point to a
+# Ruby file to directly execute. Otherwise, we just depend on PATH lookup.
+# This minor optimization can save hundreds of milliseconds on Windows.
+if ENV["VAGRANT_EXECUTABLE"]
+  Kernel.exec("ruby", ENV["VAGRANT_EXECUTABLE"], *ARGV)
+else
+  Kernel.exec("vagrant", *ARGV)
+end