Updated
AAMC Traffic Rules: The 2027 Acceptance Protocols
The AAMC traffic rules are now called the Application and Acceptance Protocols. They ask MD applicants to answer interview invitations promptly, cancel interviews they will not attend, hold no more than three acceptances by April 15 and choose one school by April 30. For the 2027 entering class, acceptances start October 15, 2026, and schools should give you at least two weeks to answer an offer through April 30, 2027.
What the AAMC traffic rules are
The AAMC publishes two matching sets of Application and Acceptance Protocols, one for applicants and one for admission officers. A footnote on both explains the old name: “these protocols were referred to as the "Traffic Rules"” by admissions officers and prehealth advisors. They cover MD and MD-PhD applicants who apply through AMCAS. The AAMC Council of Deans Administrative Board approved the current version on May 7, 2018.
They are recommendations, and each school still runs its own process. The AAMC says “These protocols are not intended to supersede the policies, timelines, or discretion of individual schools or programs.” It also asks applicants to “conduct themselves during the admissions process with the professionalism and ethics expected of a future physician”, and says personal circumstances, like a late financial aid offer, “may warrant exception from one or more of the following protocols and defers to each school's judgment in such cases”.
The eleven applicant protocols
Here is each one in plain words, in the AAMC's order. The AMCAS tool refers to them by number, as in “in accordance with Protocol 9 of the Application and Acceptance Protocols for Applicants”.
1. Know each school's rules
Follow these protocols and each school's own application, acceptance and admission steps.
2. Be truthful
Give accurate information everywhere, in your application, your interviews and after you are accepted.
3. Meet every deadline
Send primary and secondary forms, transcripts, letters and fees by each school's published deadline.
4. Keep your contact details current
Tell every application service when your address, phone number or email changes, even for a short time.
5. Plan for time away
If you will be hard to reach, name someone who can answer offers for you and tell every school who and for which dates.
6. Answer interview invitations promptly
Reply to invitations quickly, and if you cannot make a scheduled interview, tell the school right away that you need to cancel.
7. Start financial aid early
Begin the steps that decide your aid eligibility early, including need-analysis forms and, where required, your parents' tax forms.
8. Release offers you will not take
If you decide before April 30 not to attend a school that accepted you, withdraw from it promptly so the seat can go to someone else.
9. Narrow multiple acceptances
Hold no more than three acceptances by April 15 and choose one school by April 30, withdrawing from the rest.
10. Handle offers after April 30
If new acceptances arrive after April 30, promptly tell the schools you will not attend, by each school's own deadline.
11. Withdraw everywhere once you start
When you begin a pre-matriculation program, orientation or classes, withdraw from every other school.
The interview rules
Protocol 6 is the one about interviews: “Respond promptly to a school's or program's invitation for interview. If you cannot appear for a previously scheduled interview, notify the school or program immediately that you need to cancel.” Our guide to the medical school interview invite covers how to reply and schedule.
Protocols 2 and 5, and interviewing after an acceptance
Two more touch interview season. Protocol 2 reads “Provide accurate and truthful information in all aspects of your application, interview(s), acceptance, and admission processes”. What you say in the room should match your application. Protocol 5 covers travel and holidays: if you will be hard to reach, you can “delegate the authority to respond to any offers of acceptance to a parent or other responsible individual in your absence”, and tell each school who that is. Holding an acceptance does not end your season either. Until April 30, applicants who pick a school in the AMCAS tool can “continue to hold other acceptances, remain on alternate lists, and continue to interview at other schools”.
Key dates for the 2027 entering class
The protocols give a month and a day. The AMCAS page says “If you wish to start medical school in Fall 2027, please complete and submit the 2027 AMCAS application.” That puts these dates in fall 2026 and spring 2027. If a date falls on a weekend or holiday, the next business day applies.
October 1, 2026
Early Decision Program applicants hear by this date. Source
October 15, 2026
The first day MD schools may tell regular applicants they are accepted. Source
February 19, 2027
"Plan to Enroll" opens in AMCAS for anyone holding an acceptance. Source
March 15, 2027
Each school has made at least as many offers as it has first-year seats. Source
April 15, 2027
Hold no more than three acceptances. Source
April 30, 2027
Choose one school and withdraw the rest. "Commit to Enroll" opens. Source
After April 30
Schools give at least five business days to answer an offer, or two within 30 days of orientation. Source
Choosing between acceptances
Protocols 8 to 10 are about holding offers. Protocol 8 opens “In fairness to other applicants” and asks you to withdraw from a school as soon as you know you will not attend it. By April 15, keep at most three acceptances. By April 30, keep one.
How the AMCAS Choose Your Medical School tool works
AMCAS tracks this in its Choose Your Medical School tool. From February 19, 2027, “Plan to Enroll” shows schools only a count, and you can change it at any time, though “they can select only one school at a time”. From April 30 you can also pick “Commit to Enroll”, which means “By selecting "Commit to Enroll," I am indicating that I have made my final selection and withdrawn all other applications, including waitlist positions.” The AAMC adds “Selecting "Commit to Enroll" does not automatically withdraw applications from other medical schools.” You still write to each school yourself.
A second look can help you choose, and a letter of intent tells a top choice where you stand. If you are still waiting, our medical school waitlist guide covers how lists move after April 30, and how long to hear back covers decision timing.
“Why do you want to attend our medical school?”
A strong answer names two or three things only this school offers and ties each to something you have already done. Practicing it also helps you see which acceptance fits you best.
What schools promise applicants
The protocols for admission officers are the other half of the deal. Each school also agrees that by March 15 it will “issue a number of acceptance offers at least equal to the expected number of students in its first-year entering class”. For applicants, that means:
No regular acceptances before October 15.
Schools may send other decisions earlier.
Two weeks to answer, through April 30.
Until April 30, every applicant except EDP gets at least two weeks to respond to an offer.
No penalty for holding other offers.
Through April 30 you may hold other acceptances or a waitlist spot without losing anything, scholarships included.
Five business days after April 30.
After April 30 the minimum is five business days, or two business days within 30 days of orientation.
A refundable first deposit.
A school's initial deposit should be refundable at least until April 30, except for EDP applicants, and count toward tuition if you enroll.
Your letters stay confidential.
Schools should not show you your letters of evaluation, except where state law says otherwise.
In return, after April 30 a school may check that you still plan to enroll. The AAMC says “If a school is unable to confirm an applicant's intention to matriculate, the school may choose to rescind the acceptance.” Answer those messages by the date given, and our guide to the “Why this medical school?” question helps you put your reasons into words.
DO schools: the AACOMAS Traffic Guidelines
Osteopathic schools follow their own AACOMAS Traffic Guidelines. They say “COMs may begin extending offers of admission at any time after the interview.” They set a deposit schedule by acceptance date and say that “prior to May 1, applicants need to withdraw from any college(s) which they do not plan to attend and only hold a position at one COM” to avoid having positions withdrawn.
Sources
Sources: the AAMC Application and Acceptance Protocols for Applicants, the protocols for Admission Officers, the AMCAS Choose Your Medical School tool and the AACOM AACOMAS Traffic Guidelines. All checked October 26, 2026.
Frequently asked questions
What are the AAMC traffic rules?
It is the old name for the AAMC Application and Acceptance Protocols. One set tells MD and MD-PhD applicants how to handle interviews and offers. A second set tells schools how to make offers and how long you get to answer.
How many medical school acceptances can I hold?
As many as you receive until April 15. By April 15 the AAMC asks you to hold no more than three, and by April 30 to choose one and withdraw from the others. For the 2027 entering class those dates are April 15 and April 30, 2027.
Can I keep interviewing after I accept an offer?
Yes. Until April 30 you can hold acceptances, stay on waitlists and keep interviewing. Even after you choose a school with "Plan to Enroll", the AMCAS tool says you can continue to interview and stay on waitlists.
How long do I have to answer a medical school offer?
Through April 30, at least two weeks. After April 30, at least five business days, or two business days within 30 days of the start of orientation. Each school's offer letter sets its own deadline within those limits.
Do the traffic rules apply to DO schools?
No. DO schools follow the AACOMAS Traffic Guidelines, which have their own deposit schedule and ask you to hold a seat at only one osteopathic school before May 1.