What does it mean when a CSU major or campus is 'impacted'?

It means that program, academic level, or campus received more eligible applicants during the initial filing period (October 1 to November 30) than it has space to accommodate. Impaction triggers supplementary admission criteria on top of CSU's baseline eligibility index -- meeting the system-wide minimum doesn't guarantee admission to an impacted program.

Are all CSU campuses impacted?

No. Some CSU campuses are impacted at every level for every major, while others are impacted only in specific high-demand programs like nursing or engineering, and a few carry very little impaction at all. The specific list changes from year to year, so check a campus's current impaction status directly rather than assuming last year's list still applies.

Which CSU major is impacted most often?

Nursing. It's impacted at essentially every CSU campus that offers a four-year nursing program, driven by state-mandated student-to-faculty ratios and a limited number of clinical placement slots at hospitals -- a capacity constraint, not a reflection of how many students want to major in it.

What CSU 'Impacted Majors' Actually Means, and Why It Isn't the Same at Every Campus

Meeting CSU's baseline eligibility index gets you into the CSU system -- it doesn't automatically get you into the specific campus or major you actually want. That gap is called impaction, and it isn't distributed evenly across the system.

What impaction actually means

A CSU program, campus, or academic level is officially "impacted" when it receives more eligible applicants during the initial filing period (October 1 through November 30 for fall admission) than it has capacity to accommodate. Once something is impacted, the campus can apply supplementary admission criteria on top of CSU's baseline eligibility index -- a higher GPA threshold, specific completed coursework, or other campus-set requirements -- to narrow the pool down to its actual capacity. CSU's own enrollment leadership describes three distinct levels this can happen at:

Program-level impaction: a specific major, like nursing or engineering, gets more qualified applicants than that program specifically can take.
Academic-level impaction: an entire applicant pool at a level -- first-time freshmen or upper-division transfers, for instance -- exceeds a campus's capacity, independent of major.
Full campus impaction: a campus is impacted at every level, for every major, meaning even a non-impacted-sounding major still requires clearing that campus's supplementary criteria simply because the campus itself is oversubscribed.

Not every campus carries the same kind of impaction

This is the real variation students need to check directly rather than assume: as of the CSU's current impacted-programs matrix, Cal State Fullerton and Cal State Long Beach are impacted at every level, for every undergraduate program -- there is no non-impacted major or applicant pool at either campus. Other campuses carry a much narrower footprint: recent data shows Fresno State impacted in a specific list of majors (including nursing, several engineering disciplines, and agriculture-related programs) rather than campus-wide, while Cal State East Bay and Cal State LA each carry impaction in only a single named program (nursing, in both cases) with no broader campus impaction at all.

This is exactly why the same five campuses -- Fullerton, Long Beach, San Diego State, San José State, and Cal Poly San Luis Obispo -- are the ones sitting out CSU's new Direct Admission Program: four of those five are at or near full campus impaction, which makes a proactive, pre-application admission offer much harder to extend without running past actual capacity.

The one major that's impacted almost everywhere

Nursing is the most consistently impacted major system-wide -- it's impacted at nearly every CSU campus that offers a four-year nursing program. This isn't really about applicant demand outpacing interest; it's a hard capacity constraint. State-mandated student-to-faculty ratios limit cohort sizes directly, and clinical placement slots at partner hospitals are themselves limited, so a nursing program can't simply admit more students even if it wanted to. Engineering programs show up as commonly impacted too, for similar capacity-driven reasons rather than a sudden spike in interest.

The specific list changes every year -- don't rely on last year's

CSU republishes its impacted-programs matrix annually, and which majors and campuses appear on it shifts from cycle to cycle -- a major that wasn't impacted two years ago can become impacted, and vice versa. Rather than repeat a static list here that would be out of date within a year, check CSU's own current impaction database directly for your specific target campus and major before you apply.

What this means for you

Meeting CSU's baseline eligibility index isn't the finish line for an impacted major. Budget real time to research that specific program's supplementary criteria -- a higher GPA threshold, required coursework, or other campus-set requirements -- well before you apply.
If your target campus is Fullerton or Long Beach, assume every major carries some form of supplementary criteria, since neither campus has an unimpacted program to fall back on.
Nursing and engineering applicants should plan around impaction as the default assumption, not the exception, given how consistently both are impacted system-wide.
Check the current year's impaction status directly rather than trusting last year's list -- including this article's -- since CSU updates the matrix annually and specific programs move on and off it.
See our full CSU vs. UC comparison for how impaction fits into the bigger picture of how each system actually decides who gets in.