For the first time since 1880, it is now more likely for young adults ages 18-34 to live with parents than with a partner or on their own.  On average, parents also provide young adults with about $2,200 annually in material assistance—such as food, educational expenses, or direct cash assistance—throughout the transition to adulthood.

But for the tens of thousands of young people exiting or aging out of the foster care system each year, most often when they turn 18, parental support is not an option. Without parents as a safety net, these young people face a vast array of extreme disadvantages. They are more likely than the average youth to drop out of high school, be unemployed, and rely on public assistance. Many of these young adults find themselves in prison, homeless, or as parents earlier or less prepared than they would have liked. Any one of these outcomes can result in immediate and long-term hardship. For example, adults without a high school degree have an unemployment rate of 8 percent, compared to 5.4 percent for those who have one. Interaction with the criminal justice system can make it difficult to obtain employment, housing, education and training, and more. And homelessness causes and exacerbates health problems, ranging from communicable diseases to behavioral health problems.

Overall, the cost of aging out is devastating to these youth and to our society.

Since 2000, more than 340,000 young people have aged out of foster care without permanent family connections. Taxpayers and communities pay nearly $300,000 in social costs over the lifetime of the average young person who ages out of foster care. Even conservative estimates find that the overall social costs of these young people to the United States hover around $8 billion every year. Yet policymakers have real opportunities available to help some of our nation’s most vulnerable youth and save public dollars.

In an effort to address some of these challenges, Congress enacted the Fostering Connections to Success and Increasing Adoptions Act of 2008. This law permits states to receive federal support for young adults who remain in foster care through age 21, while they are working or pursuing education and training. In short, the legislation allows young people to remain connected to their foster families as they transition to adulthood.

So far, the results of the Fostering Connections Act have been encouraging. It is associated with an increased likelihood that these young people will complete at least one year of college, which can result in higher earnings. Other studies suggest that extending foster care to age 21 is related to a reduction in the number of foster youth who become homeless. Another study revealed that remaining in extended care is associated with less reliance on public assistance and a lowered likelihood of being arrested.

Disappointingly, fewer than half of states have chosen to take up the federal option to extend foster care to age 18 under this legislation. Considering the effects of aging out and the proven benefits of this additional support, this is a commonsense choice that all states should take. It not only will give some young people a better shot—it will also likely save on social costs that instead can be invested in housing, education, training, or other initiatives that support youth aging out.

The cost of the status quo is too high and the potential benefits for extending support to older foster youth are too promising for states to justify their continued inaction.