You can also use the money in your Health Savings Account (HSA) to invest in stocks and other securities, potentially allowing for higher returns over time. The key to maximizing your unspent contributions, of course, is to invest them wisely. Your investment strategy should be similar to the one you’re using for your other retirement assets, such as a 401(k) plan or an individual retirement account (IRA). When deciding how to invest your HSA assets, make sure to consider your portfolio as a whole so your overall diversification strategy and risk profile are where you want them to be.