At the most popular campuses, the non-resident admission numbers are even higher: 40 percent of this fall's freshman admits to UCLA are non-residents, 32 percent at San Diego and 28 percent at Berkeley.
UC President Mark Yudof acknowledges the sharp rise in non-resident admission but says, "Stories have been more hysterical than the facts deserve."
Actual enrollment rates of non-Californians are considerably lower than their admission rates, and the higher tuition paid by non-residents subsidizes California students, he said.
Still, the percentage of non-resident undergraduate headcount is climbing at UC's most sought-after campuses, reaching 18 percent at Berkeley last fall.
"I don't think it's outrageous," Yudof told a gathering of the Palo Alto Chamber of Commerce last month.
"It provides another form of diversity, and we also charge them a ton of money. If we charge them $30,000, I can take some of that and move it over to pay for the Californians the Legislature isn't paying for."
To avoid reducing the number of UC slots for California students, Yudof said the university has boosted the number of overall spaces in the nine-campus system.
For example, system-wide undergraduate enrollment last fall was 181,508 — 10 percent higher than it was five years ago, when it stood at 163,302.
That year — 2007 — the university, system-wide, admitted 6,283 non-resident students for the fall freshman class.
This year, non-resident freshman admits for the fall term is triple that, at 18,846. Data on the number of those who actually plan to enroll this fall is not yet available.
Yudof maintains that UC has a system-wide "cap of 10 percent" on non-resident undergraduate enrollment, instituted by the Board of Regents. But enrollment figures are much higher on the most popular campuses.
Non-residents comprised 18 percent of Berkeley undergraduates last fall, up from 13.9 percent in 2010.
At UCLA, it was 15.8 percent last fall, up from 12.6 percent the year before.
System-wide, non-resident students made up 8.4 percent of undergraduate headcount last fall, up from 7 percent in 2010, according to statistics published by Yudof's office.
In that same period, system-wide undergraduate enrollment of California residents declined a half-percent: from 167,118 in the fall of 2010 to 166,265 in fall 2011.
On a recent speaking tour of the state, Yudof made the case that the UC system is an "economic engine" for California, generating $46.3 billion in economic activity and supporting one in 46 jobs in the state.
He decried reductions of state funding for the UC system.
Last year, the Legislature funded $2.37 billion — just 10.5 percent — of UC's overall $22.5 billion budget, most of which came from revenue from the system's five medical centers.
The state covers 60 percent less per UC student than it did 20 years ago and, for the first time, students now pay more than taxpayers, Yudof said.
He called for the state to re-invest in UC, calling the system the "seed corn" for economic growth in California.
"We face hard alternatives and, the fact is, nobody wants to pay," he said. "When you get to the question of taxation and tuition, people get off our train."
Yudof rejected a suggestion that UC de-emphasize state funding and refocus on beefing up other sources.
"Taxpayers built this place, and I'm reluctant to call it quits," he said.
"We're a consummately California institution."