would graduation early affect my admission chances?

Answered

Applying to college with fewer credentials, course rigor, ECs, and 1 year less experience with clubs, sports, and classroom time certainly can affect your success, especially at the better schools, since academics are only 1 measurement of success to them.

If you are applying to a middle-of-the-road State school, their academic threshold is not that competitive, you may indeed be just as competitive as other applicants. Should you apply to elite colleges like Ivys, or near-Ivys, or the best liberal arts colleges, the majority of admits will have a leg up on you in almost every category of criteria.

I don't know what the graduation requirements are at your school but at mine, we need 25 credits to graduate which is like 6.25 courses per year for 4 years. The best students at my school all had over 25 after junior year and my friends and I have 36-40 credits going into graduation because many of us took online college courses over the summer or dual enrollment college courses through the community college. So most successful applicants to the best colleges have like 4-5 years English, 4-6 years of Math, 4-5 years of Foreign Language, 4-5 years of Science, and 4-5 years of history. This means anywhere between 6-12 APs or IB courses.

There are many factors to consider when applying to college and since I'm a White Passing Non-Hispanic, Non-Black, mixed person, I think I felt I had to have better test scores, better course rigor, better ECs, better leadership, better sports, etc because I wasn't going to get some leeway from affirmative action at the better colleges. I definitely don't resent anyone who got in with lesser grades, test scores, and ECs, because of race, socio-economic status, etc. but for my narrative, I felt it most important not to graduate early since I only wanted to go to the best schools.

I would discuss this further with some of the admissions offices of the schools you are applying to and if they feel you'll be better off staying in HS, then you have to make that personal decision with your family. Also if you have a good rapport with your guidance counselor or have some friends who have older brothers and sisters in college, I would bounce the idea off them as well.

The caveat is that there are a few prodigal geniuses that are completely bored with HS by the time they are 13 or 15 and want to go to college. In those cases, there are some colleges that have special genius programs for younger admits where they live in a more supportive dorm environment with more staff to look after them. I would say, these colleges try to create more of a boarding school atmosphere for such rare candidates. If you are a certifiable genius, I would say you have less to worry about.

Good Luck with your college admissions process.