Investing any discretionary investments you have in an investment plan or endowment policy, together with your lump sum should you choose to withdraw it, is a good way to ensure that your savings keep growing. An investment plan gives you the freedom to choose the underlying investments and to add or withdraw funds at any stage, while an endowment policy offers you a long-term investment with additional benefits like tax efficiency and estate planning. An accredited financial adviser will be able to help you make the most of any additional retirement savings you may have.