The Power of Tax-Deferred Growth Why are 401(k) plans, annuities, and IRAs so popular? Share | Related Content Tuning Your Social Security Benefit When should you take your Social Security benefit? Where Will Your Retirement Money Come From? Retirement income may come from a variety of sources. Here's an overview of the six main sources. Retirement Plan Distributions There are a number of ways to withdraw money from a qualified retirement plan.