Most healthy adults between 18 and 60 with a BMI under 32 can potentially donate a portion of their liver to someone who needs a transplant. The liver is unique among organs because it regenerates, which makes living donation possible. A person can also donate after death if their liver is healthy enough for transplant. Both paths have specific eligibility criteria, and the screening process is thorough.
Basic Requirements for Living Donors
To donate part of your liver while alive, you need to meet several baseline criteria. According to Johns Hopkins Medicine, living donors must be between 18 and 60 years old, have a BMI below 32, and be in good overall physical and mental health. You cannot have significant organ disease (heart, kidney, or lung conditions), active cancer, hepatitis, chronic infections, or active substance abuse.
Your liver also needs to be in good shape internally. If a biopsy shows that more than 20% of the liver tissue contains fat deposits, you’ll be disqualified. This is because a fatty liver doesn’t regenerate as reliably and may not function well enough for the recipient. Donors with a BMI over 30 are often asked to lose weight first and undergo a biopsy to check for this, since higher body weight correlates with liver fat.
The remaining liver after donation also has to be large enough for the donor to survive safely. If the surgery would leave you with less than 25% of your original liver volume, the transplant team will not proceed. In rare cases, donors are also turned away if their bile duct anatomy is unusually complex, which would make the surgery too risky.
Blood Type Matching
Blood type compatibility matters. Most liver transplants happen between donors and recipients who share the same blood type or have compatible types. Blood type O is considered a universal donor for liver transplants, though transplanting an O liver into a non-O recipient can occasionally cause a temporary condition where leftover immune cells from the donor attack the recipient’s red blood cells. This usually resolves on its own.
ABO-incompatible transplants (where the blood types would normally be mismatched) are possible but carry higher risks of rejection, blood clots in the liver’s arteries, and bile duct complications. These transplants are more commonly performed in children, where outcomes have been comparable to matched transplants. In adults, they’re typically reserved for emergencies like acute liver failure when no compatible organ is available.
The Psychological Screening
Donating a liver isn’t just a physical decision. Transplant centers in the U.S. use multidisciplinary teams, typically including social workers, psychiatrists, and psychologists, to evaluate every potential donor’s mental health and motivations. The goal is to make sure you’re donating voluntarily, understand the risks, and have adequate support for recovery.
Certain mental health conditions are considered absolute disqualifiers. Active suicidality, self-injurious behavior, psychosis, and active eating disorders all rule out donation at the vast majority of transplant centers. Active alcohol, cocaine, or opioid use disorders are nearly universally disqualifying, with over 93% of transplant programs listing them as absolute contraindications. An inability to cooperate with the evaluation team or follow post-surgical instructions will also end the process.
What the Medical Evaluation Involves
If you pass the initial screening, expect a comprehensive workup that typically happens in two phases. The first phase includes standard blood tests to check liver and kidney function, clotting ability, and blood sugar levels. You’ll be screened for hepatitis B, hepatitis C, and HIV. Imaging starts with an abdominal ultrasound and a specialized CT scan that maps the blood vessels in your liver and calculates its volume to determine whether enough liver can be safely removed.
The second phase goes deeper. It includes heart screening (an echocardiogram for younger donors, a stress test for those over 35), thyroid function tests, blood sugar markers, and screening for clotting disorders. Smokers and anyone over 40 will get lung function tests. If you have a family history of certain liver diseases, additional targeted testing may be required. The International Liver Transplant Society recommends cardiovascular assessment for all donors, with further cardiac imaging if anything looks concerning.
Deceased Donors
Anyone who has registered as an organ donor (or whose family consents after death) can potentially donate their liver. There is no strict age cutoff for deceased donation the way there is for living donors. What matters is the condition of the liver itself. The organ is evaluated at the time of death through blood work, imaging, and sometimes biopsy. Livers with significant disease, active infection, or widespread cancer are not used.
Deceased donor livers are tested for blood type, liver and kidney function, viral infections (hepatitis B, hepatitis C, HIV), and bacterial contamination through blood and urine cultures. The cause of death and the donor’s medical history are also reviewed, but having had certain health conditions doesn’t automatically disqualify someone. A liver from an older donor or one with minor issues may still be transplanted if it’s the best available option for a recipient in urgent need.
Risks and Recovery for Living Donors
Living liver donation is major abdominal surgery, and it carries real risks. In a large study of 393 living liver donors, about 27% experienced minor complications like wound issues or mild infections. Another 26% had more significant complications that required treatment but didn’t cause lasting harm. Serious, life-threatening complications occurred in about 2% of donors. The recorded death rate was 0.8%, with one donor dying from infection and organ failure during the initial hospital stay.
Recovery follows a fairly predictable timeline. You’ll spend roughly five to seven days in the hospital. For the first six weeks after discharge, you shouldn’t lift anything over 10 pounds. Driving is off the table for at least two to three weeks, since you’ll be on pain medications and fatigued. Most donors return to work six to eight weeks after surgery, depending on how physically demanding their job is.
The liver regenerates quickly. The most rapid regrowth happens in the first six weeks, when the liver typically reaches about 80% of its original size. Growth continues more slowly over the following months, and by one year the liver generally returns to about 90% of its pre-surgery volume.
Who Pays for the Donor’s Care
In the U.S., the recipient’s health insurance covers the donor’s medical evaluation, surgery, and immediate post-operative care. Complications related to the donation are also typically covered, though how long that coverage lasts varies by insurance plan. What insurance does not cover are the indirect costs: travel, lodging, meals, lost income, and childcare.
The National Living Donor Assistance Center (NLDAC) can help with some of these expenses. It reimburses travel and lodging costs, dependent care, and up to four weeks of lost wages after surgery. Eligibility is based on the recipient’s household income, which must be at or below 350% of the federal poverty guidelines. Donors who go through a Donor Shield transplant center may receive up to $12,000 in lost wage reimbursement (capped at $2,000 per week for six weeks) plus up to $5,000 for other out-of-pocket expenses.
Several states also offer tax deductions ranging from $5,000 to $25,000 for unreimbursed donation-related costs, including travel, lodging, lost wages, and medical expenses. The specifics vary significantly by state.