I have been seeing a lot of threads about people wanting to transfer into a top 15/20 college. The truth is everyone (more 95% of all people) who applies to the following universities is wasting their money.
DO NOT APPLY: Harvard, Yale, Stanford, Chicago, Duke, Dartmouth.
ALL of these colleges accept less than 5% of their transfer students or less. Meaning more than 19 out of 20 applicants get rejected. Princeton accepts none. Getting into Harvard as a freshman is easier than getting in as a transfer to the above schools. You can also bet athletic transfers make up a high percentage of their incoming transfer pool. Throw away your money and suffer rejection at your own choice.
Perfect applicants will be rejected: Columbia, CalTech, WashU, Northwestern, MIT, Penn.
The above colleges accept transfers, but at a rate between 5 and 10%. A 4.0 college GPA is commonplace for people who apply. You would also need a very rigorous workload in your declared major to even stand a slight chance. All applicants who are trying to compensate for bad high school grades should avoid applying altogether. Again, think about the athletic transfers.
Here is where I would say transferring starts to become a possibility instead of charity. Very strong applicants have some tangible chance of getting in, and paying the application fee might be worth the cost. Still, since the acceptance rate is between 10 and 15%, eight or nine out of ten people are getting rejected. Cornell says 21%, but then you account for the over 250 guaranteed transfers and the number begins to look more like 14%.
Many people are making threads about transferring into a high-ranked university without looking at the threads prior. Before you apply to any of the above schools, look at your grades and course load. They had better be above a 3.7 and of very challenging classes relating to your declared major, or else you're just tossing your money away. Freshmen, wait until you get your first semester grades before even considering transfer. Final exams can change everything.