Each year, hundreds of O'ahu residents — and perhaps more — pay more property tax than necessary because they don't know about exemptions that could reduce their tax bills, city officials said.

At least eight tax exemptions are available in addition to the standard exemption that every owner occupant is entitled to — but still must apply for to receive. Some tax credits also are available.

Gary Kurokawa, administrator of the city's real property assessment division, recalls several cases in which elderly residents missed 30 years worth of exemptions because they never knew to apply.

"You feel so bad they didn't know," he said.

Now is the time to find out, Kurokawa said, because there is a Sept. 30 deadline to file for exemptions for the bills that owners will receive next year.

Christie Adams of Hawai'i Kai went a year without a tax break she was entitled to because her date of birth wasn't on file when she hit age 55, a milestone that triggers a bigger exemption. With the base tax rate for improved residential homes at $3.75 per $1,000, that probably cost her about $75 that she shouldn't have had to pay on her canal-front townhouse. Adams said she only found out about the exemption because she happened to be taking a real-estate class.

Adams says it isn't fair that taxpayers have to find out about exemptions and deadlines on their own. "I think it's really the government's responsibility to promote this," she said.

Kurokawa said his staff tries to get the word out. He said the city schedules talks for seniors and other groups, but knows it isn't reaching as many as they'd like.

"We try our best, but it's not one of the priorities that the council and the administration would have," he said.

As of last year, more than 134,000 people had claimed an exemption in Honolulu. City officials said they have no way of knowing how many of the nearly 110,000 other property owners — about 243,000 total — might qualify for exemptions.

But homeowners reeling from this year's higher property tax bills are looking for ways to bring those bills down, and some are finding that they could have saved money by applying for various exemptions: homeowner/occupant, 55 and older, blind, disabled veteran, even one for those who replace their cesspools with septic tanks.

Council Chairman Donovan Dela Cruz gets lots of calls from residents complaining that they didn't know what they could get until after it was too late to apply. And he knows what that is like firsthand because he paid more property tax than necessary for two years.

"Even myself, I didn't realize that I didn't apply for a homeowner's exemption," Dela Cruz said. "At that point, it was too late for that tax bill. I had to wait for the next year."

He is planning more public education, workshops in his community and supports more outreach to the entire island.

Lowell Kalapa, president of the Tax Foundation of Hawai'i, said the 1978 Constitutional Convention transferred the property tax function from the state to the counties, but no public education campaign was set up to keep taxpayers informed.

Kalapa said the counties traditionally are tight about giving money to the property tax division, so the offices generally work short-staffed. With fewer assessors, Kalapa said properties may not be assessed to current values. And with fewer staff members to educate people about the exemptions, fewer people get the tax breaks to which they are entitled.

He said the public does need to know more because exemptions change over time and eligibility changes, too. The exemptions keep increasing from age 55 to age 70 and go even higher for some low-income elderly.

"The public really needs to be informed about it," Kalapa said.

Kurokawa said people can look up their exemptions online and can call or visit their offices. He said the city made a big effort in 1999 to solve the age issue by notifying all owners — like those in Adams' situation — whose birth dates didn't show up on property tax records.

He said the city mailed 17,000 letters to people who didn't have their birth date listed in the files and got back more than half with updated information. Still, last week his office found that 5,299 property owners still don't list that information, and as a result could miss out on exemptions to which they're entitled.

Kurokawa's advice: Don't assume that you filled out the owner-occupant exemption when you bought your property. Check before the deadline.

Exemptions are not retroactive because the money collected each year goes into the budget to pay for city services, he said, "We can't be giving back the money after the city spent it," he said.

Some exemptions must be renewed every year.

And this year two new tax breaks become available.

Homeowners have begun to sign up for new exemptions for the low-income elderly made possible by a city ordinance approved last year. Those who qualify — and apply — will get an additional tax break on the bill they receive next July, said city assistant real property administrator Robert Magota.

And a bill approved by the council this month will offer a tax credit to folks who earn $50,000 or less each year.

Kurokawa said he's not clear how many will qualify for either tax relief program.

"Any time it's income-based, we just don't know how many there are," he said "It's real difficult to determine the impact."

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com.