Many retirees look for ways to boost their retirement income as they move into a new stage of their lives. One choice is to establish a passive income stream, which needs no maintenance but offers a consistent supply of revenue. Renting out real estate, buying dividend-paying stocks, selling digital goods like e-books or courses, and setting up an online store with drop-shipping are a few passive income ideas for retirees. Real estate investment trusts (REITs) and rental properties are two more common options. Even though they need some initial investment and regular care, rental properties can eventually generate a steady stream of revenue.