How Long Is the Lung Transplant Waiting List?

There is no single number for how long you will wait on the lung transplant list, because the system no longer works that way. Under the current U.S. allocation framework, called continuous distribution, the most medically urgent candidates have a median time to transplant of just six days, while less urgent candidates wait a median of about 45 days. Those figures represent a dramatic shift from the era before 2005, when adults routinely waited well over a year simply because organs went to whoever had been listed longest. The real answer depends on your medical urgency, your diagnosis, your blood type, your antibody profile, and even your zip code.

How Allocation Policy Reshaped Wait Times

Before May 2005, donor lungs in the United States were distributed primarily by time on the waiting list. If two candidates were equally matched for blood type and location, the one who had been waiting longer got the organ. That incentivized early listing and penalized patients with fast-progressing diseases who needed a transplant urgently but had not been on the list long enough. Median wait times for adults hovered around 379 days, and for adolescents the figure was even higher at 414 days.¹ One multicenter U.S. study recorded an average wait of roughly 681 days in the pre-reform period.²

The Lung Allocation Score, or LAS, replaced the time-based system in 2005. It ranked candidates on a scale that balanced how likely they were to die without a transplant against how much survival benefit they could expect from one. The effect was immediate: median adult wait times fell from 379 days to 83 days, and adolescents saw a comparable drop to 104 days.¹ Overall wait-list time continued to decrease over the following years as transplant centers adjusted to the new scoring.³

In March 2023, the U.S. system shifted again to continuous distribution, sometimes called the composite allocation score, or CAS. Rather than hard geographic boundaries and a single priority score, continuous distribution weighs medical urgency, expected post-transplant outcomes, travel distance, and equity factors on a sliding scale. Early data from one large center showed that donor offers per waitlisted patient rose significantly, leading to shorter times to transplant without hurting outcomes after surgery.⁴ Candidates added to the list with high medical urgency scores had a median wait of just six days, while those with lower urgency scores waited a median of 45 days.⁵ And the age-based disparities that had persisted under the old system flattened out, so younger recipients no longer faced disproportionately longer waits.⁶

Your Diagnosis Shapes Your Timeline

Not all lung diseases progress at the same speed, and the allocation system is designed to reflect that. Pulmonary fibrosis, a scarring disease that can deteriorate rapidly, has historically carried the highest waitlist mortality. A European study found that fibrosis patients and pulmonary hypertension patients had the steepest death rates on the list, around half of listed patients dying, compared with about 38% for those with emphysema.⁷ A separate analysis confirmed that fibrosis patients had the highest chance of receiving a transplant but also the highest probability of dying while waiting, while emphysema patients had lower waitlist mortality overall.⁸

Under modern scoring systems, this translates into fibrosis patients generally receiving higher urgency scores and shorter waits. Emphysema patients, whose disease tends to progress more slowly, often receive lower urgency scores and wait longer, but they are also less likely to die on the list. The tradeoff is real: fibrosis patients who do get transplanted see survival benefits within the first two months, while the benefit for emphysema patients takes closer to nine months to materialize.⁷

At a single center, about 35% of all listed candidates died on the waiting list, with the highest mortality among those with interstitial lung disease, where nearly half did not survive to transplant.⁹ Time on the waitlist itself appears to be independently associated with worse outcomes after transplant, even after accounting for how sick you were when listed.¹⁰

Blood Type, Antibodies, and Biological Compatibility

Your blood type can meaningfully change how long you wait. Among candidates with lower urgency scores, those with blood type O had a 20% lower transplantation rate than those with type A, and a higher rate of dying or being removed from the list. Type AB candidates at the same low-urgency level, on the other hand, had a 52% higher transplantation rate than type A. The pattern reversed at higher urgency levels: there, types B and AB fared worse, with roughly 20–28% reduced transplantation rates compared with type A.¹¹ The reason is partly supply and demand. Type O donors can give to anyone, so their organs get spread across all recipient blood types. Type O recipients can only receive from type O donors, creating a bottleneck when urgency is low and competition is high.

Antibody sensitization is another hurdle that does not get much public attention. Your immune system can develop antibodies against donor tissue from previous blood transfusions, pregnancies, or earlier transplants. If you have high levels of these antibodies, measured by a panel reactive antibody score, the pool of compatible donors shrinks. Patients with high sensitization waited an average of about 294 days, compared with roughly 162 days for those with low sensitization and about 143 days for those with no concerning antibodies at all.¹² Sensitized patients are not just waiting longer; they also face higher mortality while waiting.

Where You Live and What You Can Afford

Geography has been one of the most stubborn sources of inequality in lung transplantation. A large cohort study of nearly 20,000 candidates found that those in areas with the lowest local donor lung availability had an 84% higher risk of dying or being removed from the list compared with those in areas with the most available lungs. Their transplantation rate was 57% lower.¹³ This is partly because lungs must be transplanted quickly and historically have been allocated within local areas first. The continuous distribution system was partly designed to address this: under CAS, organs now travel significantly farther, with a median distance of about 354 miles compared with 195 miles under the previous system, and more procurements now require a flight. Despite the added logistics, waitlist times shortened and hospital stays were shorter.¹⁴

Socioeconomic status shapes outcomes even before a person reaches the waiting list. A recent study found that patients from the most economically disadvantaged neighborhoods were about 40% more likely to die before ever being placed on the waitlist and 45% less likely to be listed at all, compared with patients from the most resourced areas.¹⁵ Among cystic fibrosis patients specifically, those with more socioeconomic barriers accessed transplant about half as often as equally sick patients with fewer barriers.¹⁶ These are not waiting-list problems in the narrow sense. They are access problems that filter out patients before the clock even starts.

Racial disparities persist as well. Between 2005 and 2021, about 82% of U.S. lung transplant candidates were White, 10% were African American, and 8% were Hispanic.¹⁷ Given that lung diseases do not respect racial lines at those proportions, the composition of the list itself reflects barriers to referral, evaluation, and listing that fall disproportionately on non-White patients.

Children Face Different Odds

Pediatric lung transplant candidates deal with a frustrating structural problem: many of them are listed at adult transplant programs. Among children and adolescents studied in one analysis, 58% were listed at adult centers, and their outcomes were dramatically worse. Only 42% of those listed at adult programs ultimately received a transplant, compared with 93% at pediatric programs. Being listed at an adult center was the strongest risk factor for dying on the waiting list, with more than fifteen times the risk.¹⁸ The reasons are partly about donor-recipient size matching (children need smaller lungs, and pediatric programs are better at identifying and accepting them) and partly about institutional experience with pediatric post-transplant care. For families navigating this system, choosing the right transplant center is one of the most consequential decisions they will make.

Single Versus Bilateral Listing

Transplant candidates with certain diseases can be listed for a single lung or for both lungs. The choice affects how long you wait. For patients with idiopathic pulmonary fibrosis, listing for bilateral transplant only meant a higher risk of dying on the list and a lower chance of receiving a transplant, compared with patients listed for a single lung or for either procedure.¹⁹ The logic is straightforward: a bilateral listing requires a size-matched pair of lungs from the same donor, which narrows the pool of acceptable offers. In emphysema, a national dataset showed that waitlist mortality was about 2.4% for single-lung candidates versus 6.2% for those listed for bilateral transplant.²⁰ There are legitimate clinical reasons to prefer a bilateral transplant in many cases, but the tradeoff in wait time and waitlist survival is one that surgeons and patients should discuss openly.

Why So Many Donor Lungs Go Unused

One reason the list moves as slowly as it does is that lungs are the hardest major organ to use from a deceased donor. The majority of potential donor lungs are declined before they ever reach a recipient. The most common reason for rejecting lungs at the time of procurement is what the surgical team sees when they look at the tissue directly: abnormalities in the lung itself account for more than half of on-site declines, followed by declining oxygenation levels and unexpected findings on bronchoscopy.²¹ Donor lungs can also be turned down earlier in the process based on imaging, smoking history, or infection risk. The more times a set of lungs is offered and refused by different transplant teams, the less likely it is to be used at all: lungs with no prior refusals had about a 57% chance of being utilized, dropping to 39% after ten refusals.²²

Two innovations are expanding the pool of usable lungs. The first is donation after circulatory death, or DCD, in which organs are recovered after the heart has stopped rather than during brain death. DCD lung recipients tend to have shorter waitlist times and comparable outcomes after surgery.²³ The second is ex vivo lung perfusion, or EVLP, a technique in which donor lungs are placed on a machine that pumps a nutrient solution through them outside the body. This allows surgical teams to assess and even recondition lungs that would have been declined under older protocols.²⁴ The acceptance of organs from hepatitis C-positive donors, who can now be treated with antiviral therapy after transplant, has added yet another source.²⁵

Multiple Listing and Gaming the System

Some candidates register at more than one transplant center, effectively placing themselves on multiple waiting lists simultaneously. This is legal in the United States, and it works: multiple-listed candidates had a 2.7-fold increase in their chances of receiving a transplant compared with those listed at a single center. But the practice is not distributed equally. Candidates who listed at multiple centers were more likely to be White, college-educated, and privately insured. Those with postgraduate education were more than twice as likely to be multiple-listed as those without.²⁶ The financial and logistical demands of maintaining evaluations and relationships at two or more centers are considerable, which means this strategy disproportionately benefits patients who already have more resources.

What Happens When You Are Temporarily Taken Off the List

Not everyone on the waiting list is actively eligible for an organ at all times. Candidates can be placed on inactive status for various reasons, from personal choice to becoming temporarily too sick for surgery. Among more than 56,000 candidates studied, about 29% experienced at least one period of inactivity. The consequences depend on the reason. Being inactivated because you were too sick was strongly associated with dying or being permanently removed from the list, carrying more than four times the risk even after adjusting for disease severity. Even after the acute episode resolved, candidates who had accumulated more than ten days of inactivity faced persistently elevated risks compared with those who had never been inactivated.

Heart-Lung Transplant and Retransplant Candidates

A small number of candidates need both a heart and lungs. These patients occupy a unique position because they compete for organs across two allocation systems. A revision to the heart allocation policy in 2018 shortened waitlist times for heart-lung candidates from an average of about 253 days to 164 days and cut waitlist mortality roughly in half. These patients were also far more likely to be on mechanical life support while waiting in the more recent period.

Retransplant candidates, people who have already received a lung transplant and need another, make up a small but growing share of the list. The proportion of new registrants who were retransplant candidates rose from about 3% in 2003 to over 5% by 2005, and the share of all lung transplants that were retransplants tracked upward over the same period. Retransplant candidates tend to be younger adults and face the added immunological challenge of prior sensitization, which can lengthen their wait as described earlier.

For candidates navigating this system, the practical takeaways are worth stating plainly. Ask your transplant team about your specific urgency score and what it implies for your likely wait. Ask whether single-lung listing might be appropriate for your disease. Inquire about whether your center participates in DCD and EVLP programs, since centers that accept these donors have a larger effective donor pool. And if you have the resources to consider evaluation at a second center, the data suggest it substantially improves your odds of receiving an organ, even though the equity implications of that reality are uncomfortable.

1
PubMed Central. Improved waitlist and transplant outcomes for pediatric lung transplantation after implementation of the lung allocation score
2
PubMed. The impact of the lung allocation score on short-term transplantation outcomes: a multicenter study
3
PubMed. Shift from time-based waiting list to the Lung Allocation Score system and its impact on wait times
4
PubMed. Impact of continuous distribution as the allocation strategy on lung transplantation
5
American Journal of Transplantation. Continuous Distribution of Lungs Decreases Waiting List Mortality without Compromising 6-Month Post-Transplant Outcomes
6
American Journal of Respiratory and Critical Care Medicine. C47-11 Impact of Age on Lung Transplant Waitlist Time Before and After Implementation of the Continuous Allocation System
7
PubMed. Listing for lung transplantation: life expectancy and transplant effect, stratified by type of end-stage lung disease, the Eurotransplant experience
8
PubMed. Lung transplant waiting list: differential outcome of type of end-stage lung disease, one year after registration
9
PubMed. Waiting List Mortality and Potential Risk Factors in Lung Transplant Candidates: A Single-Center Data
10
PubMed. Time on the waiting list is an independent risk factor for day-90 mortality after lung transplantation
11
PubMed Central. Lung transplant waitlist outcomes among ABO blood groups vary based on disease severity
12
PubMed Central. Increased Calculated Panel Reactive Antigen Is Associated With Increased Waitlist Time and Mortality in Lung Transplantation
13
PubMed. Geographic disparities in donor lung supply and lung transplant waitlist outcomes: A cohort study
14
JHLT Open. Going the distance: Geographic effects of the lung transplant composite allocation score
15
JAMA Network Open. Socioeconomic Differences in Navigating Access to Lung Transplant
16
Annals of the American Thoracic Society. Impact of Socioeconomic Position on Access to the U.S. Lung Transplant Waiting List in a Matched Cystic Fibrosis Cohort
17
PubMed Central. Racial Disparities in Waiting List Outcomes of Patients Listed for Lung Transplantation
18
PubMed. Waiting list outcomes in pediatric lung transplantation: Poor results for children listed in adult transplant programs
19
PubMed. Comparison of wait times and mortality for idiopathic pulmonary fibrosis patients listed for single or bilateral lung transplantation
20
PubMed Central. Single-lung transplantation in emphysema: Retrospective study analyzing survival and waiting list mortality
21
PubMed Central. Characteristics of Donor Lungs Declined On-Site and Impact of Lung Allocation Policy Change
22
PubMed Central. Sequence of Refusals for Donor Quality, Organ Utilization and Survival After Lung Transplantation
23
Transplant International. Trends in Donation After Circulatory Death in Lung Transplantation in the United States: Impact Of Era
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PubMed Central. Beyond the Barriers of Ex Vivo Lung Perfusion Through an Emblematic Case: A New Way Forward to Expand the Donor Pool
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PubMed. Expanding the Lung Donor Pool: Donation After Circulatory Death, Ex-Vivo Lung Perfusion and Hepatitis C Donors
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PubMed Central. Multiple Listing in Lung Transplant Candidates: A Cohort Study