Target-date funds have become the darling of retirement planning, particularly within employer-sponsored 401(k) plans where they serve as default investment options for millions of Americans. Their appeal is understandable: these funds promise a “set it and forget it” approach to retirement investing, automatically adjusting asset allocation as investors approach their target retirement date. However, when financial advisors recommend target-date funds for clients outside of 401(k) plans, they may be unknowingly imposing significant hidden costs that could substantially erode long-term wealth accumulation.