The USMLE (United States Medical Licensing Examination) is a three-step exam series that every physician must pass to get a license to practice medicine in the United States. It’s jointly managed by two organizations: the National Board of Medical Examiners, which develops the test content, and the Federation of State Medical Boards, which represents the 70 state medical and osteopathic licensing boards across the U.S. and its territories. Together, they provide a single standardized system so that every state board evaluates doctor candidates the same way.
How the Three Steps Are Structured
The USMLE is divided into Step 1, Step 2 CK (Clinical Knowledge), and Step 3. Each one tests a different stage of medical training, moving from foundational science to supervised clinical decision-making to independent practice.
Students typically take Step 1 at the end of their second or during their third year of medical school, Step 2 CK near the beginning of fourth year, and Step 3 during or after the first year of residency training. The full sequence spans roughly four to five years from start to finish.
Step 1: Basic Medical Science
Step 1 tests whether you understand the scientific foundations of medicine. The heaviest emphasis is on pathology (the study of disease), which makes up 45 to 55 percent of the exam. Physiology, the study of how the body normally functions, accounts for 30 to 40 percent. The remaining questions cover pharmacology, biochemistry and nutrition, microbiology, immunology, anatomy, histology, behavioral sciences, and genetics, each ranging from about 5 to 20 percent of the exam.
Step 1 is now scored as pass/fail rather than with a three-digit numerical score. This was a significant change for medical students, since Step 1 scores were previously one of the most influential factors in residency applications. With the shift to pass/fail, the pressure has moved toward Step 2 CK as the primary scored exam on a student’s record.
Step 2 CK: Clinical Knowledge
Step 2 CK evaluates your ability to apply clinical science in the context of patient care under supervision, with an emphasis on health promotion and disease prevention. Starting May 2026, the exam is a one-day, nine-hour testing session divided into sixteen 30-minute blocks with up to 20 questions per block and a minimum of 55 minutes of break time built in.
Unlike Step 1, Step 2 CK reports a numerical score. This makes it the primary scored exam that residency programs use to compare applicants.
Step 3: Independent Practice
Step 3 is the final exam and the only one spread across two days. It tests whether you’re ready to practice medicine without supervision.
The first day, called Foundations of Independent Practice, consists of 232 multiple-choice questions across 12 blocks, with 60 minutes per block. The total testing session runs about seven hours. The second day, Advanced Clinical Medicine, includes 180 multiple-choice questions in 9 blocks of 30 minutes each, plus 13 to 14 computer-based case simulations. These simulations give you a patient scenario and let you order tests, prescribe treatments, and manage care in real time, with each case running 10 or 20 minutes. The second day lasts about nine hours total.
Who Can Take the USMLE
Three groups of people are eligible. Students enrolled in or graduated from U.S. medical schools that grant an MD degree (accredited by the Liaison Committee on Medical Education) can register for Steps 1 and 2 CK. Students from U.S. osteopathic programs earning a DO degree (accredited by the Commission on Osteopathic College Accreditation) are also eligible. International medical graduates, or IMGs, qualify if their medical school is listed in the World Directory of Medical Schools and meets the criteria set by the Educational Commission for Foreign Medical Graduates (ECFMG).
For Step 3, all applicants need passing scores on both Step 1 and Step 2 CK, plus either a completed MD or DO degree from an accredited U.S. or Canadian school, or ECFMG certification for international graduates.
What International Graduates Need to Know
If you graduated from a medical school outside the United States, you need ECFMG certification before you can enter a U.S. residency program. This involves several requirements beyond passing the USMLE steps.
Your medical school must be listed in the World Directory of Medical Schools with a specific ECFMG notation confirming it meets eligibility standards. You must have completed at least four credit years of medical education at that school. ECFMG will verify your diploma directly with your medical school and request your official transcript.
Beyond passing Step 1 and Step 2 CK, you also need to meet a clinical skills requirement and a communication skills requirement. This is done through an ECFMG Pathway, which includes passing the Occupational English Test (OET) Medicine. Previously, a now-discontinued exam called Step 2 CS fulfilled this requirement, and passing scores from that exam still count if they remain valid.
Fees and Attempt Limits
As of 2026, the application fee for Step 1 is $695, Step 2 CK is $695, and Step 3 is $955. These fees cover the exam registration only. Many students spend additional money on prep courses, question banks, and study materials, which can add hundreds or thousands of dollars to the total cost.
You get a maximum of four attempts per Step, and that includes incomplete attempts (for example, if you started the exam but didn’t finish). If you fail a Step four times, you become ineligible to take any Step in the USMLE sequence, which effectively ends your path to U.S. medical licensure. There’s also a pacing rule: you can’t take the same Step more than three times in a 12-month period, and your fourth attempt must be at least 12 months after your first attempt and at least six months after your most recent one.
Score Reporting and Timelines
Results are typically available two to four weeks after your test date, though occasional delays happen. The USMLE recommends allowing up to eight weeks when planning around score release, particularly if you need results for residency applications or licensing deadlines. Step 1 results come back as pass or fail. Step 2 CK and Step 3 report numerical scores along with a pass/fail outcome.