Ask your employer if they offer a non qual plan. It's a form of deferred compensation that doesn't qualify for the 401k tax code and can be used in addition to traditional 401k. A non qual can reduce your immediate tax liability and even grow through investment choices. It's usually only available to corporate officers, executives, or other highly compensated employees, and not all companies offer it. Consult a tax or investment advisor before enrolling as there are different forms of non qual plans and some carry significant risk should your employer become insolvent.