Graduate School - Letters of Recommendation

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How important are letters of recommendation?

Letters of recommendation are required for almost every graduate school application and are a very important part of the application process. 

How many letters of recommendation do I need?

Although it can vary, generally, you will be asked for three letters. We recommend that you send only the number of letters requested. Admissions committees do not have enough time to read extra credential.

Whom should I ask for letters of recommendation?

The best letter writers are those that know you well and can provide an evaluation of your ability to perform and succeed at the graduate level. Check each graduate program's website to see if they require letters from specific individuals. Those who work in graduate and professional school admissions tell us the following generally make the best letter writers:  


  • Someone who knows you well
  • Someone with the title of "professor"
  • Someone who is a professor at the school granting your baccalaureate degree
  • Someone who has earned the degree which you are seeking in your graduate work
  • Someone with an advanced degree who has supervised you in a job or internship aligned with the graduate program you are pursuing
  • Someone who has academically evaluated you in an upper-division class

Note: Letters from family friends, political figures, and the like are discouraged and, in fact, may be detrimental.

How do I approach potential letter writers?

First, make a list of professors and/or supervisors who will be your best advocates. Then, set up an appointment to discuss your request in person. Do not make the request via email if possible. Be prepared to articulate your interest and reasons for attending graduate school. Letters of recommendation are written strictly on a voluntary basis. The best approach is to ask potential letter writers if they are willing to write you a strong letter. If you sense reluctance or the answer is no, ask someone else.

When should I approach letter writers? What if I plan to take some time off before I go to graduate school?

Professors and supervisors are generally pleased to write on your behalf, however, they are usually involved in many activities. Faculty are especially busy during the months of November and December. Be considerate of your letter writers’ time and approach them at least two months before you need the letter.


If you plan to take some time off before going to graduate school, don’t wait until you want to apply to graduate school to ask for letters. Your professors could be on sabbatical or you may not be fresh in their minds anymore. You can ask professors for a "general" letter of recommendation before you leave Cal and ask that they keep the letter in a safe place or send it to a letter service for safe keeping (see below for more information). When you are ready to apply to graduate school, contact the professors again and ask them to update your letters.

How can I go about getting good letters of recommendation?

Since your best letters will come from those who know you well, make an effort to get to know your professors and/or supervisors. A few ways you can do this are to speak up in class, select courses with small class sizes, take more than one class from a professor, do research for a professor, take on optional projects, and regularly attend office hours.

The best strategy you can use to get a good letter of recommendation, particularly if a professor hasn't known you long, is to provide your letter writer with ample information about you. This way, you will get a letter that includes concrete details about you instead of a letter that contains only your grade, which is of limited value. 

The letter writer should make it clear how they know you and how well. The writer should be as specific as possible about your relevant academic skills and personal traits. The writer should also put you in perspective with other students the writer has recommended in the past, such as, "I have taught at Cal for X years and during that time have recommended X# for grad school. I put this student in the top X percent." The more detailed a letter, the more it reflects the writer's direct knowledge of your work and potential and the more credible it will appear to members of the admissions committee.

If you ask a faculty member or GSI to write you a letter, they may not feel comfortable saying "no" even if they don't feel able to write a strong endorsement. Give them another option. Rather than asking if they'd write you a letter, you can ask if they feel they know you and your work well enough to write a good letter. This allows them a graceful out and saves you from having a letter with faint praise.

What information do my letter writers need to write good letters?

You can help your letter writers write enlightening letters by giving each of them a portfolio comprised of:

  1. A cover note that includes:
    • Information on how to get in touch with you in case they need to reach you
    • A list of schools to which you are applying
    • What you would like emphasized in the letter(s). Check your specific graduate program's letter of recommendation guidelines. If there is specific information being requested, advise your letter writer to include this information.
    • Links to or information on where they can submit the letters
    • Due dates for the letters with the earliest due date at the top
    • Any other information that is relevant
    • Open and close your note with thanks, acknowledge that the letter writer’s time is valuable, and include how the letters are important to your professional future.
  2. Recommendation forms - to make it easy for your letter writer to complete forms in a timely manner, complete the following:
    • Type in your applicant information
    • Type in the recommender’s name, title, and contact info (telephone, email, address, etc.)
  3. Your unofficial (telebears) transcripts (note the courses you took with them)
  4. A draft of your statement of purpose
  5. A copy of your best work in the course (with instructor comments on it), lab evaluations, projects, etc.
  6. Your resume

Can I ask my GSI for a letter?

Yes, you can, but as a general rule it is better to have letters written by professors rather than GSIs. The professor may be in a better position to evaluate you and to compare you to current and previous classes of students. GSIs often write fine letters and frequently write parts or all of letters which professors sign or co-sign. Having a GSI’s letter co-signed by a professor adds to its strength, especially if the professor can add useful comments.

However, it is better to have a strong letter from a GSI than a letter from a professor that says little or nothing. Ultimately, because some graduate schools specifically state that they will only accept letters from professors, it is in your best interest to get to know your professors well enough so that they can write a strong recommendation letter for you.

If you must get a letter from a GSI, strategize with the GSI to draft a letter of evaluation then forward it to the professor, using the pronoun "we" instead of "I." For example, the GSI could write, "We saw Mr. Conner struggle before the midterm and we were impressed with his tenacity and capacity to master the material." Then, the letter can be signed by both the GSI and professor at the bottom of the page.

In addition, sometimes GSIs are willing to provide some written insight or notes for the professor so that the letter can be written and signed solely by the faculty member. You will need to give your portfolio to both the GSI and the professor and see how they want to do business.

Do graduate schools care if letters are confidential or not?

In general, graduate programs prefer confidential letters. Admissions officials say that it displays more confidence on the part of the applicant if letters are "confidential" (meaning that you cannot see or read the letters).

Why should I use a Letter Service?

A Letter Service, such as Interfolio or Virtual Evals, will store your letters of recommendation in one place and send them to schools on your behalf. Your letter writers will write one letter and fill out one form rather than filling out a different form for every application. You will need to inform your letter writers of the letter writing guidelines for the Letter Service you plan to use (see your letter service's website or contact them directly for more information).