The Waiting List

If the medical evaluation shows that you’re a good candidate for a transplant but you don’t have a family member or friend who can donate a kidney, you’ll be put on the transplant program’s waiting list to receive a kidney from a deceased donor - someone who has just died.

Every person waiting for a deceased donor organ is registered with the Organ Procurement and Transplantation Network (OPTN), which maintains a centralized computer network linking all regional organ gathering organizations (known as organ procurement organizations, or OPOs) and transplant centers. The United Network for Organ Sharing (UNOS), a private nonprofit organization, administers OPTN under a contract with the Federal Government.

UNOS rules allow patients to register with multiple transplant centers. Each transplant center will probably require a separate medical evaluation, even if a patient is already registered at another center.

Observers of OPTN operations have raised the concern that people in certain regions of the country have to wait longer than others because allocation policies for some organs give preference to patients within the donor’s region. Kidneys, however, are assigned to the best match regardless of geographic region. The Federal Government continues to monitor policies and regulations to ensure that every person waiting for an organ has a fair chance.

Waiting Period

How long you’ll have to wait depends on many things but is primarily determined by the degree of matching between you and the donor. Some people wait several years for a good match, while others get matched within a few months. The average waiting time for a kidney is three to five years, depending on blood type.

While you’re on the waiting list, notify the transplant center of changes in your health. Also, let the transplant center know if you move or change telephone numbers. The center will need to find you immediately when a kidney becomes available.

OPOs are responsible for identifying potential organs for transplant and coordinating with the national network. The 69 regional OPOs are all UNOS members. When a deceased donor kidney becomes available, the OPO notifies UNOS, and a computer-generated list of suitable recipients is created.

Suitability is initially based on two factors:

1. Blood type. Your blood type (A, B, AB, or O) must be compatible with the donor’s blood type.

2. HLA factors. HLA stands for human leukocyte antigen, a genetic marker located on the surface of your white blood cells. You inherit a set of three antigens from your mother and three from your father. A higher number of matching antigens increases the chance that your kidney will last for a long time.

If you’re selected on the basis of the first two factors, a third is evaluated:

3. Antibodies. Your immune system may produce antibodies that act specifically against something in the donor’s tissues. To see whether this is the case, a small sample of your blood will be mixed with a small sample of the donor’s blood in a tube. If no reaction occurs, you should be able to accept the kidney. Your transplant team might use the term negative cross-match to describe this lack of reaction.

Getting on the national waiting list:

1. Get a referral from your physician.

2. Contact a transplant hospital. For a comprehensive list of important statistics about transplant hospitals, including contact information, click here to search your zip code for the nearest transplant center.

3. Choose a transplant hospital which fits your needs after discussing insurance, geographic location, financial aspects.
Get an evaluation at the facility to determine if you are a good candidate.

4. Ask lots of questions during your evaluation to determine if you and the hospital and the transplant team are a good fit.If you are a good candidate (as determined by the transplant team) you will be added to the waiting list for kidneys.

The transplant hospital will let you know you have been successfully added to the list within 10 days. Questions about your status on the list should be directed to them, not UNOS.

Many people waiting for a transplant incorrectly believe they are added to the bottom of the list – having to wait for others higher on the list to get a transplant before they get to move up. This is not the case.  The list is in order of matching priority according to length of time waiting, blood type, and tissue type. The list is blind to age, sex and race.

Even though one person has been on the list longer than another, it doesn’t necessarily mean they move up the list.  For example, if a waiting recipient has blood type O, their name will not be on the list to get an organ from a donor with blood type B – they are incompatible. Even though one may have waited longer than another, it doesn’t ensure they get the next available organ.

Changes to the current allocation system?

The OPTN/UNOS Kidney Transplantation Committee has been charged with reviewing - and potentially improving - the current kidney allocation system, which has been in place for 20 years. The committee is now considering the following three concepts which would work together to determine a candidate Kidney Allocation Score (KAS):

1. Life Years from Transplant (LYFT): Determines the estimated survival that a recipient of a specific donor kidney may expect to receive versus remaining on dialysis. LYFT is primarily a measure of utility.

2. Dialysis Time (DT): Time spent on dialysis allows candidates to gain priority over the period they receive this treatment, adding the essential element of justice into the allocation system.

3. Donor Profile Index (DPI): Provides a continuous measure of organ quality based on clinical information. DPI increases individual autonomy by providing a better metric for deciding which organs are appropriate for which candidates. LYFT, DPI, and DT are incorporated so that kidneys are matched to candidates based on the expected survival of both the kidney and the recipient.

Currently, the concepts are under review by the U.S. Department of Health and Human Services (HHS) Office of Civil Rights (OCR). The OCR is assessing whether the concepts are consistent with applicable federal laws, including the Age Discrimination Act.


Some people awaiting a kidney transplant will take their case to the media. While this can raise awareness of organ donation overall, it will not help their chances of receiving a deceased donor kidney. It can be helpful in the process for a living donation if the message falls upon the right ears. However, media coverage (or letters to a physician) has no influence on the allocation of available organs. All matches are made from the UNOS national registry. Preferential treatment does not exist.




Number of kidney transplants performed in the United States. Learn More