How to Request a (Math) Recommendation Letter

Table of Contents

• Introduction and advice from others
• What is the point of a recommendation letter anyway?
• Will I ever need a recommendation letter? (YES)
• Who should I ask for a recommendation letter?
• When should I ask for a recommendation letter? (ASAP)
• How should I ask for a letter? (Nicely)
• A sample letter
• Should I remind the letter writers about upcoming deadlines?

Introduction and advice from others

At some point in your career (earlier than you think!) you will need a recommendation letter. Perhaps you are applying for an REU, grad school, a conference, a job,… and you need one or more people to vouch for you. Who should you ask and how do you ask for a letter? You are essentially asking someone “hey how do you really feel about me, and would you be willing to put it in writing?” and that’s a daunting thought. The goal of this post is to help you navigate this delicate situation.

The first piece of good news is that all of us have asked for letters of recommendation in the past, and we are all grateful to those who wrote letters for us, which opened many doors. Surely, I have a long list of people to thank for their letters over the years! So we are well aware of the power and the need for strong recommendation letters, and we want to do our best to help others advance their careers. In light of this, we expect that we will be asked to write recommendation letters, and many of us consider letter-writing as part of our mathematical community good citizenship.

The second good piece of news, particularly for someone like me writing a post about this topic, is that there is a lot of great advice already available online on how to ask for recommendation letters. Here is a few such pages, in no particular order. They will give you an idea of what most people are looking for before writing a letter of recommendation:

• Michael Orrison (Harvey Mudd College).
• Tara Holm (Cornell University).
• Tom Roby (UConn).
• Keith Conrad (UConn; his page is probably the most comprehensive).
• Megumi Harada (McMaster University).
• Ravi Vakil (Stanford University).
• Rob Pollack (Boston University).
• Joseph Silverman (Brown University; also a very thorough page).
• David Zureick-Brown (Emory University).

Notice that many of these people give credit to each other for the advice in their pages. I thank all of them for putting all of their advice in a public place!

The summary of all the advice below (TL;DR): ask mathematicians that know you well, and have a reason to think highly of your potential. Ask for a letter well in advance. Give a lot of detailed information to your letter writers (about you, deadlines, requirements, etc). Be patient.

What is the point of a recommendation letter anyway?

Why do we require recommendation letters in the first place? From my point of view, letters of recommendation are meant to assure that (a) the candidate is a good fit for the position or program they are applying for, and (b) the candidate has the appropriate preparation to thrive in the position or program. In addition, many programs are overwhelmed by a large number of applicants, so the letters help the selection committees while deciding what candidates will benefit the most from participating in the program. The letters of recommendation are rarely the only data point of an application, but a good recommendation letter can add a new dimension to a candidate’s file that would not fit well in other parts of an application (CV, cover letter, statements, etc.).

Will I ever need a recommendation letter? (YES)

Yes. You will absolutely need a recommendation letter at some point. Therefore, it does not hurt to think strategically and ahead of time: who will be my letter writers when the time comes? Please read the rest of the document with this question in mind, and try to network and build professional relationships with mathematicians who will later be in a position to write a strong letter for you. I also wrote about networking in this previous post about applying for jobs in math.

Who should I ask for a recommendation letter?

My first piece of advice is that you will probably need more than one letter, so you should think of who all your letter writers will be, before you start asking for letters. Each letter could discuss a different dimension of your background, so choose a variety of letter writers that can speak to a number of different parts of your application. Also: talk to someone (e.g., your advisor) about who you plan to ask for letters, and discuss your options.

The best recommenders are people that:

• know you well, from a mathematical point of view;
• expect that you will ask for a letter of recommendation at some point. In other words, it should not come as a surprise that you are asking for a letter of recommendation from said person; and
• are in a position to write a great letter about you. This means that the writer knows you well, through a mathematical experience that demonstrates your great potential.

Here are some examples of people who would be good options for a letter:

• Your academic advisor. If you have had a good relationship with your advisor, they probably know you best, and they know about your strengths, and your struggles. An advisor can give a holistic point of view that most others are not typically capable of.
• A professor you took a (math) class from (and did very well in it). A professor can speak about your work ethic, the quality of your work, and about your enthusiasm for the material. If you did not do great in their class, or if this was a very large class and you had little interaction with the professor, then they are probably not the best choice for letter writing. Ideally, this would be a math professor, but professors from other subjects can also write for you.
• A mathematician you worked/collaborated with. If you were part of an REU, an independent study, a senior thesis, a research project, and you worked with alongside another mathematician on some sort of mathematical project, then they are probably a good choice for a letter writer. As in the previous bullet point, they can speak about your work ethic, the quality of your work, and about your enthusiasm for the material. In addition, they can speak about your potential as a colleague or member of a mathematical community or department.
• A mathematician that knows about your skills and your background for other reasons. Perhaps you have been in contact with a mathematician for other reasons than those mentioned above. As long as they know you relatively well, from a mathematical point of view, and there is no clear conflict of interests in their relation to you, then they can be a good candidate for letter writer.

The people who are the wrong choices are the complement of those described above:

• People who barely know you, no matter how well-known they are in their field, are not good choices. They will not have much to say about you, and they will probably reject writing a letter for you anyway. If they did write a letter, it would be an impersonal letter at best, and it may do more harm than good.
• People who are at your own level. For example, if you are a student, do not ask another student to write a letter for you. Even if they know you well, letter readers are looking for impartial observers that are capable of summarizing your potential from a higher ground. For example, for tenure cases, all (or most) letters should come from professors with tenure or above.
• People who are family, friends, or close relations. If the letter writer cannot be an impartial judge of your potential, then the letter itself is worthless.
• People who are known to be harsh letter writers. There is no need to risk it. If you know that a person is a tough critic, then ask a letter from someone else.
• People who you are not sure they can write a great letter about you. If you have doubts about whether the would-be letter writer knows you well enough, then they do not know you well enough, and you should ask someone else.

When should I ask for a recommendation letter? (ASAP)

This one is easy: as soon as humanly possible. That early? Yes. You can let them know months in advance (“at some point I will ask you for a letter of recommendation, if you don’t mind”) for generic letters, and as soon as you can when it is game time and you know you will need a letter for a program, grant proposal, job, or what have you.

At the very least, try to give a letter writer two weeks notice, but keep in mind that many people require 3 weeks or more to write a (good) letter. It also depends on the type of letter: an email message with a paragraph about the candidate can be a quick job, but a letter of recommendation for a job search can be very time consuming and the letter writer might need a month or more.

“What?? Who takes a month to write a letter?” you might say. Keep in mind that mathematicians receive many such requests, so it is not the case that the letter takes a full month to write, but that the person might need a month to find the time to piece all the parts of the letter together for you. Professors can be very busy, particularly during letter writing season, so please be understanding that they will need as much advance notice as you can give them to be able to write the best letter possible for you.

Sometimes, however, you find out about an opportunity and need a letter in short notice, and that’s fine – it happens. Then, let the potential letter writer know that this is the case, and let them decide whether they can produce a letter in a short period of time.

How should I ask for a letter? (Nicely)

This one is an easy one as well: nicely! Seriously. Just ask nicely. Most frequently, people will ask for a letter of recommendation by email. Ideally, you would ask them first in person… though there are not a lot of in-person opportunities these days (I am writing this during a pandemic). But the truth is that asking for a letter of recommendation is a hard thing to do, and email is a good medium to put together a well-thought out request for a big ask. Also, an email message gives the recommender time to think about it and respond once they have made up their mind about whether they are an appropriate person to write a letter for you.

Here are the things you need to include in your initial message when you request a letter of recommendation:

• An introduction to remind the person of who you are, and how they know you (be specific). If you don’t think they’ll remember who you are after a brief introduction… then they are probably not a good choice. For example, “Dear Professor X, you were my professor in real analysis last semester, and I really enjoyed your class. …”
• Briefly, why do you need a letter? For example, “… The reason I am writing to you is that I am in the process of getting ready to apply for REU programs. …”
• A nice request to write a letter for you. Include a date when a letter is due. It is important to ask for a strong letter of recommendation. For example, “… and I was hoping to ask you if you could write a strong letter of recommendation for me. The first deadline for a letter is on Jan 1st. …”
• Be as specific as possible about the program you are applying for, what is needed, and when it is needed. For example, “… I am applying to this program in particular, [URL], which has a deadline of Jan 1st for letters of recommendation. Letters need to be sent by email to this address [email address] with the subject line “Letter of Rec. for [student’s name]”.
• Attach to your message basic documents that almost all letter writers will want to see before writing a letter, or even when considering writing a letter. For example, “… I have attached to this message my CV, an unofficial copy of my transcripts, and a draft of my statement of purpose. …”
• Feel free to add details about you that you would like writers to highlight in the letters. If you have received an award, or have relevant experience for the program you are applying for, or you have published a paper on the subject, etc., then let the writers know, in case they want to mention this in their letter. For example, “… I have been doing an independent study on the same topic of the REU with Professor Y, so I think this program would be greatly beneficial for my career. … ”
• Ask them what do THEY need from you. First check their website, to see if they have a section precisely about writing letters of recommendation. Otherwise, ask them to tell you what would they need to write a letter for you. For example, “… If you are willing to write a letter for me, let me know if there is anything else you need from me.”
• Thank them for their time, and wait. For example, “… I would really appreciate it if you could find the time to write a letter for me. Thank you!”

A sample letter

Here is the message once again, in one piece:

Dear Professor X,

You were my professor in real analysis last semester, and I really enjoyed your class. The reason I am writing to you is that I am in the process of getting ready to apply for REU programs and I was hoping to ask you if you could write a strong letter of recommendation for me. The first deadline for a letter is on Jan 1st.

I am applying to this program in particular, [URL], which has a deadline of Jan 1st for letters of recommendation. Letters need to be sent by email to this address [email address] with the subject line “Letter of Rec. for [student’s name]”.

I have attached to this message my CV, an unofficial copy of my transcripts, and a draft of my statement of purpose. I have been doing an independent study on the same topic of the REU with Professor Y, so I think this program would be greatly beneficial for my career.

If you are willing to write a letter for me, please let me know if there is any other information you need from me. I would really appreciate it if you could find the time to write a letter for me.

Thank you!

Should I remind the letter writers about upcoming deadlines?

As a deadline approaches, you might be wondering if your letter writers have submitted their letters on time. Luckily, many online application system will tell you if the letters have been submitted, so you don’t have to bother your writers.

Your initial message requesting a letter of recommendation should be very informative, with a breakdown of all the deadlines, so the letter writers should have all the information they need, and most of the time the letters will arrive on time. If you want, you can ask your writers early on if they would like reminders. Or if you see that a deadline is approaching and a letter has not been submitted, you may want to send a friendly email reminder about the deadline. That is usually fine, and many times welcome, because during busy times some of these things can be forgotten in a pile of other things to do. But avoid pestering your writers with too many messages and reminders!

Good luck!