MADISON, Wis. -- Tuition will rise 5.5 percent on most University of Wisconsin System campuses, but low-income students should be shielded from the impact under a budget approved Thursday.

Under a $2.2 billion annual operating budget approved by the Board of Regents, tuition will go up by $617 at the state's flagship school UW-Madison, $359 at UW-Milwaukee and about $280 at 11 other universities.

The increase is higher at UW-Madison because students will pay the first $250 of a $1,000 tuition surcharge being implemented over four years. First- and second-year students at UW-La Crosse will pay $500 more under a similar plan to improve quality.

For the first time, the budget protects students from families who earn less than the state's median of $60,000 by promising enough state and federal grants to cover the tuition increases. At UW-Madison, students from families with incomes of up to $80,000 should be shielded.

The 18-member board governing the 174,000-student system approved the plan on a voice vote during a meeting in Madison. It is the third straight year the board has approved a systemwide tuition hike of 5.5 percent.

UW System President Kevin Reilly said the "modest and predictable" increase was needed to avoid drastic cost-saving measures such as cutting enrollment or eliminating popular programs. Campuses will still be forced to tighten their belts with larger class sizes and cuts in student services, he said.

"Make no mistake, the next several years are going to be very difficult on our campuses," Reilly said.

Wisconsin should be commended for holding down tuition in the face of steep budget cuts and protecting low-income students, said Becky Timmons, a spokeswoman for the American Council on Education.

She said schools across the country, public and private, are considering different ways to "insulate the poorest students from the effects of tuition increases."

"They are recognizing that families are struggling" in the recession, she said.

The board's two student members split on the proposal.

Regent Kevin Opgenorth, a UW-Platteville student, said the increase would "price people out of higher education" even as cuts devastate campuses.

But Regent Aaron Wingad, a UW-Eau Claire student, called the budget "the responsible way to move forward."

The budget freezes tuition at 13 two-year colleges for the third straight year and for all graduate students from other states. System officials say those tuition rates were too high and kept the schools from being competitive.

Student fees for services and activities will rise by an average of 5.8 percent ($51) while room and board rates will jump 5.3 percent ($284). Many of those increases will pay for building projects, such as new residence halls and renovated student unions, approved by students.

The lean operating budget cuts $50 million in state aid, freezes salaries and requires eight days of furloughs for all UW System employees.

Guidelines approved by the board also direct campuses to slow down hiring and travel while they make plans to cut or merge unpopular or redundant academic programs.

The furloughs will save the system $17 million, which will be used to reduce the amount of cuts.

Regents President Chuck Pruitt said he worried the furloughs, which amount to a 3 percent pay cut, will make the system's below average salaries for faculty and staff even less competitive.

"We'll need to ask them again to hang in there in the hopes of better days ahead," he said.

The budget does set aside $5 million to retain star faculty members, particularly those who receive offers from other schools.

Reilly also said a law change that allows the system to offer domestic partner benefits to gay and lesbian employees will help recruitment and retention.