What percentage of applicants on a wait list for masters program generally get accepted? My application has been put on the wait list at my top choice institution (unfunded masters, about 10% acceptance rate). The Department said they may not be able to let me know the final decision until after April 15 (which I understand). However, I need to know the decision before April 15 to respond to other offers. In order to determine my chance, I have the following questions:


While this may vary depending  on the programs, is there a general percentage of applications out of the entire pool being put on wait list? If not what factors determine this?
Are wait listed applicants ranked? if not, how do programs determine which one to accept off wait lists?
Should I let them know that they are my top choice and if accepted I will almost surely attend?
The answers to your questions depend on the university/department, but are all reasonable questions to ask. It would be perfectly reasonable to send an email along the lines of


  Thank you for letting me know about the wait listing decision. I understand how competitive the admissions process is. I wanted to let you know that XXX is my top choice and if offered a place I would accept it immediately. As I have also received an offer from YYY that I need to respond to by April 15, would you mind if I checked on my status closer to the deadline?


This will hopefully open a dialog and they might say something like "given your place on the wait list it is unlikely we will know anything prior to the deadline" or "given your place in the wait list the picture should be a lot clearer closer to the deadline.