Emergency rooms are the front-door to the U.S. healthcare system. A combination of systemic issues converge in ERs, leading to long wait times and inefficiencies for patients.
Nationwide, the average ED visit was 2 hours and 42 minutes from April 2022 through March 2023, according to CMS data. That's up from 2 hours, 35 minutes in 2021, and 2 hours, 18 minutes in 2014. In Washington, D.C., wait times reached a national high of over 5 hours.
What factors contribute to lengthy ER wait times and visits? Here are some key considerations, though this list is not exhaustive:
1. The shortage of primary care physicians pushes patients to the ER for non-emergent care. This shortage, which dates back decades, shows no signs of easing. By 2033, the U.S. could face a deficit of 21,000 to 55,000 PCPs. With over 100 million Americans struggling to access primary care, the ER often becomes the default option for medical attention. This brings a host of health needs through the ER doors that could be treated in lower-acuity, more cost-effective settings if there were better access to PCPs.
2. Intensifying behavioral and mental health needs strain the system further. ED visits for mental health and substance-use issues have been on the rise for years. From 2011 to 2020, mental-health related ER visits soared for children, adolescents and teens, adding pressure on already overwhelmed emergency departments. It's now not uncommon for teenagers to spend nights waiting in ERs, sometimes for days, as they await openings in the appropriate treatment programs. Pre-pandemic, one study out of UCSF found that ED visits made by adults with alcohol and substance use disorders increased by 30% in the pre-pandemic years of 2014 to 2018.
"The public has increasingly complex health issues, such as delayed diagnoses without primary care, substance use and mental health," Christopher Kang, MD, former president of the American College of Emergency Physicians, told Becker's in 2023. "These issues have been ignored now for 20 to 30 years, in addition to boarding."
3. ER boarding is exacerbated by limited inpatient bed capacity. Boarding occurs when patients are held in the emergency department after admission to the hospital because no inpatient beds are available. Any emergency patient can end up boarded, regardless of condition, age, insurance status or location. Those in mental health crises can be left waiting for months in overcrowded ERs, hoping for an available psychiatric inpatient bed.
Last year, ED boarding reached a point where ACEP led the call to declare this crisis a public health emergency, joined by numerous medical associations and patient groups. Earlier this year, monthslong boarding problems in Massachusetts hospitals intensified to a point where the state health department declared parts of the state "high risk" due to hospitals operating at max capacity and dozens of patients spending the first night of their hospitalization in the ED on a daily basis.
4. Staffing imbalances hinder efficient patient flow. While primary and emergency medicine physicians might be the most obvious places to examine for shortages, ER visits are complicated by weak spots through the continuum of the roles and workers needed to move patients through the system efficiently. This includes nurses, on-call specialists, technicians and support staff. An insufficient combination of staff — not only a shortage of any single role — contributes to inefficient throughput in the ER. The ability to efficiently move patients through the system hinges on having the right mix of staff to handle the diverse and unpredictable range of cases.
5. The wide range of patient acuity complicates triage. Triage staff quickly assess and prioritize patients based on the severity of their conditions. This process sets the stage for the entire clinical visit.
Mistriage is a real risk in ERs. One study based on 5 million patient visits at Kaiser Permanente Northern California emergency departments found the emergency severity index — a triage method used by more than ⅔ of hospitals in the U.S. — underestimated the severity of patient conditions 3% of the time and overestimated severity about 25% of the time.
Emergency rooms are already rife with nonlinear processes, frequent interruptions and constant re-prioritization of tasks. When the acuity spectrum of patients in the ER spans from minor issues like sprains or colds to life-threatening emergencies such as heart attacks or severe mental health episodes, the triage process operates under even greater pressure, making it increasingly difficult to efficiently allocate scarce resources.
6. ER environments can be deceiving, obscuring how swamped they really are. Not long ago, headlines captured the story of a nurse who dialed 911 for help from her own overcrowded ER, which had become so packed it resembled a busy airport gate. Across the U.S., many ER waiting rooms and hallways appear visibly crowded. Yet the real issue isn't always about space — it's about staffing.
Overcrowding is frequently misinterpreted as a matter of physical capacity, when the root cause is often a shortage of personnel. Even in an ER that looks quiet, insufficient staff, unavailable specialists, or overextended nurses and physicians can lead to significant delays. These less visible factors can slow patient flow, resulting in long waits, care backlogs and a strained ER — no matter how many empty seats there might be in the waiting room.
7. The outlook for emergency medicine recruitment is also concerning. Traditionally, the specialty has maintained a stable pipeline with few unfilled residency slots. However, in 2022, one in four emergency medicine residency programs had unmatched positions, nearly 8% of available slots. This situation deteriorated in 2023, with the number of unfilled positions reaching 554 — over 18% of all offered slots — affecting nearly half of residency programs nationwide. Although most of these positions were filled later during the Supplemental Offer and Acceptance Program, the trend raised concerns about the specialty's stability and appeal. In 2024, emergency medicine had 3,026 positions, filling 2,891 of them for a 95.5% fill rate, an increase of 13.9 percentage points from the previous year.