Caltech requires letters of recommendation from two teachers or instructors during your last two years of high school. One letter each from the subjects below:
We recommend requesting letters from teachers who taught you in your final two years of high school, who know you well, and can speak knowledgeably about your skills and performance in their classroom. We would like your humanities or social science teacher to comment on your writing skills, so be sure to ask a teacher from a class with a significant writing component.
If you are an international applicant and have not taken a humanities/social science course in your final two years of secondary school, e.g. A-level students, you can substitute the required letter of recommendation from humanities/social science with another letter from a teacher in a different STEM subject, regardless of subject.
Here are examples of classes that meet our requirements for letters of recommendation:
While Caltech believes we only need 2 letters of recommendation as part of your application, students sometimes submit an additional recommendation letter that provides a significantly different evaluation than the other two letters. If you have an additional recommendation letter from a coach, mentor, employer, etc., we welcome the submission.
You can also submit a supplementary letter from a teacher or professor who did not submit one of the required recommendations. It can be from an additional STEM course or any course outside those listed for STEM or humanities/social science requirements.
We prefer that your recommender submit the letter through the application platform you used to apply. Only if this is not possible, your recommender may email the letter directly to our office at [email protected]. Emailed letters must include your full name and date of birth.
If you are submitting a research paper, we require an additional recommendation from someone who can comment on the research experience that produced the paper. This letter can come from a supervisor, a mentor, an adult collaborator, or an administrator. Research papers and posters may be uploaded to your Caltech application portal, the Beaver Breakroom after submission of your application.
After the application deadline, you will receive a link to the Beaver Breakroom, which will include instructions on submitting research projects. If you are submitting research, you are required to fill out a form with a description of your research and the email address of your recommender. Our office will then email your research recommender a link to upload their letter.
Documents such as letter of recommendation and additional letters must be submitted by a school official/recommender. We do not accept these documents if they are submitted by an applicant/student. We prefer that recommenders submit their letter through the application platform an applicant used to apply to Caltech. Only if this is not possible, a recommender may email a PDF of their letter, the applicant's full name, and date of birth to [email protected].