The cost of a private school education in Hawaii continues to climb as the state’s larger independent schools are charging 5 percent more in tuition, on average, for the upcoming school year, according to a Honolulu Star-Advertiser analysis.

Increases at individual schools range from a low of $239 at Kamehameha Schools’ three campuses — where tuition costs $5,023 for secondary students — to $2,178 at Saint Louis School. Tuition at the all-boys campus is $15,500, a 16 percent increase over last year.

Hawaii Preparatory Academy in Waimea remains the state’s most expensive private school (excluding special-purpose schools), with day tuition for high school students increasing by 3.5 percent to $23,900.

Punahou School, the state’s largest single-campus private school, comes in second with tuition of $22,050, followed by Mid-Pacific at $21,050 and ‘Iolani School at $20,900.

Tuition at these schools is almost the equivalent of the cost of annual tuition at the state’s private universities. Full-time undergraduate tuition at Hawaii Pacific University is $22,160 for the 2015-16 academic year and $21,780 at Chaminade University for most majors.

As in previous years, private school officials cite increasing personnel costs to attract and retain high-quality teachers and staff with competitive wages and benefits as the main driver behind tuition hikes. Most schools also point out that tuition doesn’t cover the full cost of educating students, noting that endowments, fundraising and philanthropy help subsidize the cost.

At least one school is not raising tuition. Island Pacific Academy in Kapolei is holding tuition flat at $15,675 for its high school grades.

During the economic downturn, most private schools tried to keep tuition flat or raised it at most by 2 percent or 3 percent. Since then, tuition has gone up in larger chunks.

Still, private school tuition here tends to be cheaper than on the mainland. For the 2014-15 school year, national median tuition for 12th grade was $24,402, according to the National Association of Independent Schools. Tuition at some New York private schools topped $40,000 in recent years.

At ‘Iolani, where tuition is going up by 4 percent, Head of School Timothy Cottrell said the school’s Board of Governors strives to keep increases to a minimum amid rising operating costs.

"Our main expense is wages for faculty and staff," Cottrell said. "We really can’t outsource like other businesses. If we give a cost-of-living increase, that really pushes tuition."

The school, which touts small class sizes, has 190 full-time teachers and a student-to-teacher ratio of 10-to-1 with enrollment at approximately 1,900.

As tuition has gone up, so have ‘Iolani’s financial aid offerings.

In each of the last three years, Cottrell said, the school’s board has increased financial aid support by twice the rate of tuition increases. For example, the school has budgeted $4.3 million for financial assistance for families in 2015-16, up 8 percent from last year — double the 4 percent increase in tuition.

Nearly 1 in 4 students receive need-based financial aid from the school.

"One of our big commitments is access to an ‘Iolani education," Cottrell said. "We’re doing everything we can to meet the needs of families who want to send their kids to this school."

John Field, Punahou School’s vice president and treasurer, also cited rising personnel costs. The school this year also rolled a previously separate technology fee into base tuition.

"The bulk of our costs, almost 70 percent, are personnel costs. That would be salaries and benefits, the biggest, of course, being medical insurance," Field said. "We’ve conscientiously tried to be as tight as we can, because we want to limit tuition increases to the absolute minimum for our parents. We understand that, at $22,000, it’s a very significant investment and we take that responsibility very seriously."

Punahou, with enrollment exceeding 3,600 students, has budgeted $5.5 million for financial assistance for families. Roughly 1 in 6 students gets need-based support.

At Sacred Hearts Academy, the state’s largest all-girls school, Head of School Betty White pointed to higher personnel costs spurring a 5 percent tuition increase to $13,309 for high school grades.

"We’re always sensitive to the economy. But it has to be balanced by competitive salaries, employee benefits and professional growth for teachers," White said. "Also, maintaining facilities, technology initiatives, quality programming — it all comes with a price."

She said the school, where 35 percent of students are on financial aid, has seen demand for tuition support increase.

"Some of the bigger schools, they’re putting a lot of money into financial aid and that affects the smaller schools like us," White said. "The big difference is we cannot meet the total need of families. For our families, we try to meet about a third of their need. … Other schools can meet the full need, which can be attractive."

At Damien Memorial School, President Bernard Ho said tuition is rising by 4 percent to $12,375 to help pay for new computers, energy-efficient lighting in classrooms and to expand athletic programs.

The formerly all-boys campus has seen enrollment nearly double since going coed in the 2012-13 school year to 680 students this year.

Even with tuition increasing every year, demand is strong at isle private schools. Hawaii has the highest percentage of private school enrollment in the nation.

Close to 20 percent of school-age kids attend private schools here, roughly twice the national average of 10 percent, according to U.S. Census data. The rate is even higher in Honolulu, where more than 37 percent of children are enrolled in private schools.

And many schools have waiting lists of students eager to snag a spot.

Punahou, for example, generally has 4.5 applications for every opening, Field said. ‘Iolani’s Cottrell said the school has waiting lists for every grade.

Carrie Hoomanawanui said she and her husband make sacrifices every year to afford to send their two children to ‘Iolani.

"It is a struggle, but we feel that is the best place for them to be. We won’t take that family vacation or do other things just so that they can be there," she said.

Hoomanawanui, a legal clerk at the city prosecutor’s office, said she and her husband, who works in the construction industry, receive some tuition assistance from the school but still pay a considerable amount out of pocket. Both parents are public school graduates.

Their son entered ‘Iolani in seventh grade and is now a junior, while their daughter entered in sixth grade and is now a sophomore.

"We’re very lucky because the numbers work out," Hoomanawanui said. "Academically and socially, everything is top-notch. When they graduate, they will be ready for college. They’ve been pushed to their limits. And while they’ll be well-educated, the hope for ‘Iolani School is to also have them leave there being a good person and responsible adults."

Punahou alumna Kristi Koga said she and her husband recognize the need for regular tuition increases and don’t view them as a huge deterrent to sending their sons to Punahou.

"It’s not surprising," she said of the increases, "but it does give us pause, to re-evaluate our expenditures as a family. It’s not easy, but it’s a sacrifice we’re willing to make because we know the value in it."

Koga, who works part-time as a consultant, and her husband, who works in law enforcement, have a son entering seventh grade and an older son in college who graduated from Punahou. She said they’re hoping their youngest son will get into Punahou in the fourth grade, the same year the two older boys enrolled at the school.

"I’ve always known the value of what the school provides — the education, the facilities, the tradition, the camaraderie. The level of everything there is something I’m willing to invest in as a parent," she said. "The decision to send them there was an easy one."

By comparison, the amount the state spends to educate students enrolled in public schools varies because the Department of Education is required to educate all students, regardless of ability or special needs.

Overall, the department spends an average of about $14,600 per student, based on a breakdown of operating expenses for regular DOE and charter schools, including employee fringe benefits and debt service. The figures do not include state spending on capital improvements or facility maintenance for schools, which is typically covered by state-backed bonds.