Everyone agrees organ donation saves lives. So why don’t more people do it?

A Vox reader asks: Why are so few people organ donors? Why would someone choose not to be a donor? Everyone agrees it’s a good thing but very few people actually do it.

Grab your ID out of your wallet. Does it have a heart on the front or back? If so, you’re one of 170 million Americans who’ve signed up to donate their organs after death. That’s about 60 percent of all eligible adults in the US — hardly “so few people.”

But if most Americans support organ donation and many have registered, why do we still have over 100,000 people waiting for transplants, with 13 people dying every day?

The gap between support and actual donations comes down to the two different ways one can donate their organs and the surprising quirks and issues particular to each.

First is after-death donations, where someone signs up to donate their organs after they die. The biggest bottleneck here isn’t registration — it’s medical.

Only about three in 1,000 people die in circumstances that allow for organ donation, according to the nonprofit Donor Alliance. To remain viable for transplant, organs need continuous blood flow right up until surgical removal, which means dying in a hospital, on a ventilator, typically from brain death, with your heart still beating through mechanical support.

When someone dies at home or in an accident without immediate medical care, crucial organs like kidneys, liver, and heart begin suffering irreversible damage within minutes of blood flow stopping. This incredibly narrow biological window rules out most deaths.

So, that 60 percent registration rate sounds impressive until you realize that only a tiny fraction of those will die in a way for their organs to be viable for a transplant.

And even when someone dies in the right circumstances, families can sometimes still block donations because they’re unsure about what their loved one really wanted, they fear bodily disfigurement or feel that the donation process is too lengthy. Legally, a person’s registration should be binding, but hospitals often won’t proceed if families strongly object. This happens in less than 10 percent of cases involving registered donors, but it still represents lost opportunities.

The other way is living donation, where you donate a kidney or part of your liver while you’re alive.

Here the numbers get really interesting. When surveyed, 86.6 percent of Americans say they might consider donating a kidney while alive, according to a 2023 survey. Yet, only about 7,000 living-donor transplants happen annually, and fewer than 350 go to complete strangers. And the number of donors haven’t changed much in the past two decades.

This gap between stated preference and actual actions reveals something fundamental about human psychology. When your sister or aunt needs a kidney, she has a face, a relationship, a story you’re privy to. You’ve probably watched them struggle through dialysis, made hospital visits with them, and watched them grow sicker.

But the 100,000 people on transplant waiting lists remain abstract statistics. Turns out, the psychological distance between “helping my sister” and “helping stranger #47,832 on a waiting list” is huge, especially at the potential costs to your body or to your wallet. Even though donating a kidney is safe for most healthy adults, it can be daunting to imagine the physical duress of going through surgery and recovery for the benefit of somebody else.

Even when people overcome these psychological hurdles, there are practical barriers at play. Living donors face average costs of $900 to $19,900 in the first year after surgery. While the recipient’s insurance covers medical expenses, donors have to handle lost wages, travel costs, and child care on their own. And they are asked to take up this burden with the goodness of their heart alone.

Also, the evaluation process to see if you’re fit to give away a kidney can take months and involve dozens of medical tests, mental health screenings, and meetings with transplant teams. Although, initial data from a pilot study found that once people register, the vast majority stay committed throughout the evaluation process.

Perhaps most tellingly, only about 16 percent of Americans had ever thought about living kidney donation. Unlike deceased donation, which people encounter when renewing driver’s licenses, living donation exists outside most people’s serious consideration.

But what about the 40 percent who haven’t registered for an after-death donation? Some of it is simple inertia; you have to actively opt in, either online or at the DMV, and many people who support the idea in theory never get around to actually signing up.

Others have genuine concerns rooted in medical mistrust, particularly in Black and Hispanic communities that have complicated relationships with the health care system. (Unfortunately, these same communities have much higher rates of kidney disease due to diabetes and hypertension, so they’re disproportionately represented among people waiting for transplants.)

Some religious groups also have concerns — certain Indigenous American groups prefer to keep the body intact after death, and some families worry about religious compatibility with donation — though most major faiths actually support organ donation as an act of charity.

There’s also the fundamental newness of it all. Safely moving organs from one person to another has only been possible since the 1980s, when we developed drugs to prevent organ rejection. Given this relatively recent innovation, organ transplantation simply has not had enough time to become a deeply familiar practice. It’ll take time for something this new to feel completely routine.

All of this creates a cascade effect. Most people support organ donation in theory, but fewer actually register. Of those who do register, only a tiny fraction die in circumstances where their organs can be used. And even then, families sometimes say no. For living donation, the drop-off is even steeper. Lots of people say they’d consider it, but very few actually follow through, especially when it comes to helping strangers. Add in the financial costs and months of medical testing, and you’re left with a trickle of actual donors.

But, there’s hope on the horizon.

The End Kidney Deaths Act, which was reintroduced in Congress in April, would give kidney donors a $10,000 annual tax credit for five years. The policy has overwhelming public support and could save an estimated 100,000 lives in its first decade. And it’s one of the few things that could meaningfully address the deaths of 47,000 people each year waiting for kidneys. My colleague, Dylan Matthews, made a moral case for this act.

If you’re interested in reading more about living donation or interested in becoming one, read this another fantastic piece that Dylan wrote about his experience of giving away a kidney to a stranger.

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