If a prospective college student is unable to find a place to decline acceptance via an online portal this letter can be sent to a university admissions office letting them know the student will not attend.
Dear Mr./Ms. Officer,
I wanted to let you know that I will not be attending University Name. I was unable to find a response option in the online portal, so I am sending this as a letter. I hope that by declining a spot, I am opening up a place on the waitlist for someone else.
I appreciate being accepted to University Name, but I ultimately found that another institution more closely matched my academic goals as well as my financial situation.
Thank you for the opportunity.