Medical School Timeline (All 4 Years Explained)

Medical school is four years, but no two years are alike. MS1 will shock you with the volume. MS2 will grind you down with Step 1 pressure on top of a full course load. MS3 throws you into a hospital and expects you to figure it out. And the first half of MS4 is its own challenge entirely, especially if you’re going into a competitive specialty.

Most premeds know it’s hard. What they don’t know is that each year is hard in its own way, or which one they’ll actually look back on as some of the best of their lives.

First Year (MS1 or M1)

The first year will be the most radical transition for most students. Gone are the days of college, and now the rigors of medical school are thrust upon you. If you’re in medical school, you’ve studied for tests and exams before; however, the sheer volume of material will take some time to adjust to.

It’s for this reason that studying in medical school is often described as drinking out of a fire hydrant. Additionally, understanding which information is essential amid a sea of details and facts is a skill you’ll fine-tune as you progress through your schooling.

The first few weeks to months are challenging; however, you’ll soon get in the groove and learn that your first year offers you more free time than any other year of medical school.

Content-wise, the material may vary from school to school. Some schools have a traditional curriculum, where you learn all of the physiology (or what’s normal) across all organ systems first, then how it can be abnormal (pathology), and then how to treat it (pharmacology).

Other schools use a systems-based approach, with blocks that last several weeks dedicated to specific organ systems, such as cardiovascular, pulmonary, gastrointestinal, etc. You will study physiology, pathophysiology, and pharmacology specific to that organ system, and repeat this format for the next system block. Several other disciplines are sprinkled throughout your curriculum. Master them now, because you’ll need this knowledge for Step 1 and beyond.

This is your year to figure out your study strategies, find your routines, optimize efficiency and effectiveness, and build your group of friends. It’s also the time to figure out whether those friends are people you can actually study with. Sometimes your closest friends are more distracting than motivating.

You’ll remember the middle and end of first year as some of the best times in medical school. The stress is comparatively low, you have more free time, and you’re bonding with people who could become lifelong friends. You’ll be amazed by your classmates, as medical students are some of the most impressive and diverse people you’ll come across.

Second Year (MS2 or M2)

Historically, MS2 begins with an uneasy tension that grows and expands throughout the year. That tension is because of one thing and one thing only: USMLE Step 1. Step 1 is the first of the three United States Medical Licensing Exams, or USMLEs, that you’ll be taking prior to obtaining your medical license. Step 1 and Step 2 CK are taken during medical school.

As of January 2022, the USMLE Step 1 exam is pass/fail. The goal of this change was to improve well-being and decrease burnout among medical students. Since USMLE Step 1 will be graded as pass/fail, it will no longer be the primary determinant of one’s competitiveness as a residency applicant.

In the second year, you will have honed your study strategies and time management, so you’ll be ready to increase the intensity of your studying. In the first couple of months, you may be solidifying your plan for studying for USMLE Step 1. Your study approach has two stages: the lead-up period during regular coursework, where you reinforce concepts using resources like Anki and UWorld, and the dedicated period when you go all out.

Medical schools are undergoing major curriculum changes to accommodate Step 1 moving to pass/fail. Most students take Step 1 in the spring at the end of their second year, which concludes their preclinical studies. In the fall and winter of your second year, you’ll hunker down and spend more time studying and less time socializing.

Of course, aim to pass Step 1 on your first attempt to keep yourself on track, keep residency options open, and establish the foundation that you will build on for Step 2 in third year. Remember, Step 1 lays a foundation for your knowledge of clinical shelf exams and USMLE Step 2 CK. If you have a stronger foundation on Step 1, you’re much more likely to perform better on Shelf exams and Step 2.

Third Year (MS3 or M3)

Most students love third year, and some students hate it. It’s an adjustment for everyone. Third year marks the beginning of your clinical years. While the first two years take place mainly in the classroom, the latter two years are primarily in the hospital or clinic. This is what you came to medical school for: to become a doctor and take care of patients.

Clinical rotations are particularly challenging because, for the first time in your life, you’re not just studying out of books and taking tests. You still have to do that, but now most of your waking hours are spent in the hospital or clinic, and the evaluations from your seniors hold tremendous weight in your overall grade. It’s a different game entirely.

Every medical student must complete a series of core rotations before graduating. During your third year, you’ll likely be rotating on internal medicine, family medicine, general surgery, psychiatry, neurology, pediatrics, OB/GYN, and emergency medicine.

For clinical rotations, you can expect:

• You’ll be helpful to your interns, residents, and other team members by helping write notes, seeing patients, and presenting on rounds.
• You’ll be in the OR assisting with surgeries by retracting, suctioning, and occasionally suturing and knot-tying.
• You will function as a member of the healthcare team and learn the clinical skills necessary by observing the residents and doctors you work with.
• You will still have to study, as all students have a Shelf exam at the end of each rotation.

Shelf exams are standardized tests taken at the end of each clinical rotation that assess your knowledge of that specialty. Think of them as miniature versions of Step 2 CK focused on whichever rotation you just completed. Combined, they cover the same ground as Step 2 CK.

Your clinical hours are long and start very early. You’re presenting patients, writing notes, and trying to impress evaluators while simultaneously studying for shelf exams. If you combined all of your shelf exams together, you’d essentially get a Step 2 CK exam.

And here’s the added challenge: You’re also preparing for USMLE Step 2 CK, which has become the single most crucial standardized test score for matching into residency. Step 2 is similar to Step 1, except it tests the culmination of your third-year medical school knowledge. The most heavily tested concepts are from your internal medicine rotation.

Programs use Step 2 CK as the primary objective metric to screen and compare thousands of applicants. Top specialties like dermatology and orthopedic surgery now average Step 2 scores of 257. Most students take Step 2 CK at the end of third year or the beginning of fourth year, though your school’s curriculum will determine the exact timing.

Students take Step 2 CK at the end of third year or early fourth year. But third year doesn’t just end with Step 2. It’s also when you start preparing your residency application. While you won’t submit until September of fourth year, the groundwork begins now, like securing letters of recommendation, drafting your personal statement, and finalizing your application materials.

Balancing clinical rotations, shelf exams, evaluations, and Step 2 CK preparation makes third year one of the most demanding years of medical school. Also, keep in mind that between the third and fourth years, some students choose to take a medical school gap year to focus on research, especially if they’re interested in highly competitive specialties that have ballooned in research expectations.

Fourth Year (MS4 or M4)

Many people say that fourth year is a dream, and that everything is smooth sailing. Not so fast. The first half of fourth year is arguably the hardest part of the entire medical training process, at least if you go into a competitive surgical subspecialty.

Your core clerkships are complete, and most of your rotations around this time are electives, which usually means they are no longer graded and are most likely pass/fail, though this varies by school. They no longer carry as much weight as they once did, but that doesn’t mean M4 will be easy.

The first half of your fourth year is challenging for two main reasons: sub-internships and preparing your residency application.

Sub-internships, also known as away rotations or audition rotations, are rotations you perform at other institutions anywhere in the country. A sub-internship in medical school is essentially a month-long interview. You have to be on your best behavior. Your sub-internship is an opportunity to show a program that they should take you into their residency. To accomplish this, you must show up early, stay late, and work hard to make the lives of the residents easier. If you’re going into a specialty with a suboptimal lifestyle, like surgery, expect long hours and high stress.

Medical students apply to residency using ERAS, which stands for the Electronic Residency Application Service. Following the ERAS application timeline, the application usually opens around June, with most students submitting in September. It’s a single common application, just like AMCAS, and you submit a personal statement, letters of recommendation, and a work and activities section. It’s very similar to AMCAS, but thankfully, you don’t have any secondaries to complete.

The timing of residency interviews varies by specialty, occurring anywhere between October and February. At the end of February, you submit your rank list. You don’t get accepted by programs in the traditional sense. Instead, both applicants and programs submit a rank list via the NRMP. An algorithm runs, and around the middle of March, Match Day arrives.

You open your envelope with the rest of your classmates during a grand ceremony, and your fate is sealed. Inside that envelope is the program you’ll be training at for the next three to seven years.

After March, it’s smooth sailing. Residency starts on July 1st. Between Match Day and starting residency, most students take this opportunity to travel or spend time with loved ones because residency is going to be a rough ride.

Which Year of Medical School Is the Hardest?

Every physician answers this differently. MS2 gets the most votes because Step 1 prep runs on top of a full course load at the same time. MS3 is a different kind of hard, less about memorization and more about physical exhaustion and learning how to function in a hospital. MS1 catches many students off guard with the sheer volume after years of being high achievers. The first half of MS4 is brutal if you’re going into a competitive surgical subspecialty.

Which year is hardest depends on the student. Some crumble under the volume of preclinicals. Others handle the classroom fine, but struggle once they hit rotations. There’s no universal answer.

Putting It All Together

Medical school consists of four rigorous years of studying and training, and no two years are alike.

First Year (M1)

• Preclinicals: learn about the body, diseases, and how to treat them.
• Comparatively lower stress
• Adjust to the volume of study material
• Hone your study strategies and build routines
• Optimize your efficiency

Second Year (M2)

• Finish the remainder of preclinicals.
• Complete USMLE Step 1 exam
• Time management is critical
• More time spent studying and less time socializing
• Many schools are shifting to a one and a half year preclinical curriculum

Third Year (M3)

• The beginning of your clinical years includes a series of core rotations
• Complete shelf exams for those rotations
• Most of your waking hours are spent in the hospital or clinic
• Still need to study when you are home from rotations
• A balance between tiring and rewarding
• Complete USMLE Step 2CK exam

Fourth Year (M4)

• Difficult, but easier than previous years.
• Especially difficult for those pursuing a competitive subspecialty
• Complete sub-internships (also known as audition rotations)
• Prepare your residency application (ERAS)
• Residency matching on Match Day

The four years of medical school are no joke. You’ll be tested, and you’ll have your lows, but you may also remember medical school as some of the best years of your life. This is thanks to the bonds you’ll make with your newfound friends, the amount of knowledge you’ll gain, and the sense of accomplishment you’ll have from completing the most rigorous professional degree in the world.

Start Strong Before You Even Get There

Medical school will test you in ways you can’t fully prepare for. But how you set yourself up during your premed years determines how much runway you have when things get hard.

The Premed Roadmap to Medical School Acceptance walks you through each year of college with a detailed, adaptable plan built to maximize your chances of getting into a top medical school. If you’re still in the premed stage, this is where to start.