"Proposing" vs. "Declaring" a Major
“Proposing” a major is simply indicating an interest in a major. “Declaring” a major is a more formal process that you go through with your department or major adviser. If you listed a major on your UC application, it initially shows as a “proposed” major in the MyUCSC portal (you may have updated this with your college adviser since filing your admission application). Students can update their proposed major online. Students who enter UCSC as frosh are expected to confirm their proposed major by the end of their first year, and be formally declared in a major by the end of their second year (or equivalent). Students who enter UCSC as junior transfers are required to be declared by the deadline in their second term of enrollment.
You do not need to wait until your second year (or second term, for transfer students) to declare. You can (and should!) declare a major as soon as you’ve decided and met the major’s qualification requirements and/or prerequisites.
Researching a major's requirements early is important, so that you can be sure to take the necessary classes to both meet the major's qualification requirements and to confirm your interest in and ability to succeed in the major.