
Hey Cooper, It is rarely too late to switch in junior year, but the timeline depends on how much overlaps with your new major and on course sequencing. Run a What-If or degree audit in your student portal, select the new major, and print the list of remaining requirements. Check your catalog year and the major map, and note which prerequisites are fall only or require multi term sequences. Then meet your current advisor, the new department advisor, and the registrar to lay out a term by term plan to 120 credits and see the graduation date impact. Ask about prerequisite overrides if you can take a course concurrently to avoid waiting a full year.
To reduce delay, try to have old major courses count as electives or toward a minor, file course substitution petitions, and use summer or winter terms to catch up on sequences. If your school allows it, finish lower division or general education at a community college using the transfer equivalency tool, and consider CLEP or departmental credit by exam for language or intro courses. Watch residency and upper division minimums, and confirm your financial aid SAP status and the 150 percent time rule so extra credits do not jeopardize aid. I switched from mechanical to computer science at the start of junior year and used calculus, physics, and linear algebra to satisfy the CS math and science core, took Data Structures in summer, and had Numerical Methods approved as a technical elective. That plan put me one semester behind, which was worth it, and I started internship prep early since recruiting in CS kicks off a year ahead.