@MrElculver2424: OP asked a general question about switching majors and later in the thread asked about specific schools such as UC Santa Barbara and SLO. The answer is that it depends upon each school’s policy. Some schools make it easy to switch majors and some do not. OP has a lot of threads going and I think they want to be told that no matter what they do, they will be guaranteed their choice major at their choice school which will lead to their choice job. No one can give that kind of guarantee.
Couldn’t have said it any better myself @Gumbymom! 
That is probably true at any selective college. (Open admission community colleges can be a different story, since they do not regulate enrollment through a selective admission process.)
Typically, this is due to capacity limits. When a given major is enrolled to its full instructional capacity, the school or department cannot leave it as an open major and not have enough instructional capacity to teach all of the students. In the short term, they choose to regulate entry into the major to keep it from exceeding instructional capacity. Of course, they could also add instructional capacity, but that tends to be a longer term project, and may involve long term commitments (e.g. tenured faculty, building additional labs or other facilities, etc.).
so is it better to apply to a more selective major first or apply to a less competitve one, bc if u apply to a more competitive major first u can switch out?
@SREE33 apply to the major you want if you get in great! If not then look at other schools you get into. There isn’t a game to all this. You have gone back and forth with mat sci and Chem e. Decide what you want and go with that. You need passion in engineering because it really is difficult. Why do something for 4 years you hate. You want to wake up each day and be like “wow what am I going to learn today!?”
i know its not a game
but idk which to apply to as primary
is it easier to transfer out of chemE to another engr major or MSE?
does anyone have an idea about swithhcing from engineering to science at UCSB?