Putting the Pension Back in 401(k) Plans: Optimal versus Default Longevity Income Annuities

Most retirees take payouts from their defined contribution pensions as lump sums, but the US Treasury recently moved to encourage firms and individuals to convert some of the $15 trillion in plan balances into longevity income annuities paying lifetime benefits from age 85 onward. We evaluate the welfare implications of this reform using a calibrated lifecycle consumption and portfolio choice model embodying realistic institutional considerations. We show that defaulting a fixed fraction of workers’ 401(k) assets over a dollar threshold is a cost-effective and appealing way to enhance retirement security, enhancing welfare by up to 20% of retiree plan accruals.