Acceptance of admission

Each campus that accepts you for admission will issue you a Statement of Intent to Register (SIR) form or direct you to a website where you can declare your intent to register. Use this form or website to indicate whether you accept or decline the admission offer.

You are strongly encouraged to wait until you hear from each campus you have applied to before you declare your intent to register.

Transfer students admitted for fall must submit the SIR by June 1.

For most campuses, the SIR submission process is online. However, if you are required to mail a paper SIR form, it must be postmarked by these dates. Applicants admitted at a later date or for the winter or spring term should respond by the deadline indicated in the offer of admission.

You may accept admission to one campus only. You may not transfer your acceptance from one campus to another after you declare your intent to register. A $250 nonrefundable deposit must accompany your acceptance.

Source:  https://admission.universityofcalifornia.edu/how-to-apply/applying-as-a-transfer/after-you-apply/admissions-decisions.html