I want to apply to Amherst college (My hard reach school) and they only accept TOELF or IELTS scores. Alternatively, I can submit proof that I have attended my last four years of high school in a school with primary language as English (I have). Every other college I am applying to accepts Duolingo Test Scores so I was planning to just apply for the English test waiver for Amherst and submit my DET scores elsewhere (Since it's so much cheaper than the other tests).
My concern is, will it hurt my chances of admission?
The only reason I can think of that it could possibly hurt you was if you scored badly on any of the proficiency tests but clearly that is not the case. I would email the school directly and ask what they recommend. Ask them if you can skip the test as your school's primary language is English and if not ask how you can apply for the waiver.
Applying for an English proficiency test waiver shouldn't hurt your admission chances! Like @Melokenzie said, I would reach out to Amherst and ask them how to proceed. I anticipate that they might let you skip the test since your high school's primary language was English, which would indicate that you are proficient.
If your primary medium of education is English, technically you don't have to submit proficiency test scores anywhere. If you still want to submit, then I don't think that's going to be a major factor. You aren't asking for a waiver here, you are proficient in the language, so you aren't submitting test scores. This should never hurt your chances.
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