Nu'uanu resident Suzanne Ching was among hundreds of O'ahu taxpayers who called the city last month after she realized she was missing out on $100,000 in property tax exemptions — a problem she read about in The Advertiser.

Ching said her late husband used to claim an exemption, but after he died in 2001 the exemption somehow got left off. Ching, who is 65, just found out she qualifies for multiple exemptions: the basic $40,000 homeowner's exemption, plus age-related breaks that took that up to $100,000.

When she went to the downtown office of the city real property tax assessment division to file her paperwork to get it fixed, she spoke with others in line who didn't know what they had to file.

City assistant real property administrator Robert Magota said hundreds of people have called their offices and that about 5 percent of them are changing their exemptions.

"A lot of the claim forms that came in have yet to be pro-cessed," Magota said, so it's too early to tell how many people actually changed their exemption.

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. Property tax exemptions reduce the taxable value of a home or other real property, which in turn lowers the homeowner's tax bill.

Last year more than 134,000 people claimed an exemption in Honolulu. City officials said they have no way of knowing how many of the island's 109,000 other property owners — about 243,000 total — might qualify for exemptions.

"If this had not come out in the paper, I would not have been aware of that and it would have gone on," Ching said. With property tax values shooting up in recent years, she and others are more keenly aware of trying to find ways to reduce the bill.

City property tax officials last month said hundreds of residents don't apply for exemptions that could lower their tax bill. That information sent hundreds to the phones and computers to find out if they are getting what they should.

Ching said she hopes that others will check before the Sept. 30 deadline to apply for exemptions.

City Council Chairman Donovan Dela Cruz has been working with senior citizen groups and others to tell people about the exemptions through community workshops.

He said at a Wahiawa workshop his staff met at least two widows who are eligible for paying the minimum $100 annual tax but were paying more.

"That passes on to the surviving spouse," Dela Cruz said. He said the response from the community has been very positive as people in Kahuku, Wahiawa, Whitmore Village and Pupukea have learned about how they can get some help.

Dela Cruz said a number of homeowners found they weren't getting what they should because they didn't have their birthdate information on file so they weren't getting age-related breaks that begin to kick in at age 55. "If they don't have your birthdate on record, you don't get an increased exemption as you get older," Dela Cruz said.

His office has two more public meetings scheduled in Kane'ohe and Wahiawa on this hot topic. "Obviously, there was a need for this," Dela Cruz said. "People really, really appreciate it."

Nanakuli resident Alfredo Villamor found out this month that he qualified for double his exemption because of his age. The 62-year-old postal worker has owned his home for 30 years and could have qualified for the age-linked increases for the past seven years.

He went to one of the meetings set up by Dela Cruz and found he wasn't getting what he should. "Gee, I'm losing out," he said, and has since corrected his paperwork.

Wahiawa resident Joy Vane got quite a shock when she received a property tax bill for $1,300 after years of paying only the $100 minimum tax because her husband was a veteran with a total disability. He passed away in 2001 and this year she got the 2005-06 bill for the full amount.

"I said, 'Wow, what hap-pened?' " she said.

Then her mother went to a community meeting arranged by Dela Cruz and the city officials helped her to straighten out the confusion.

Vane is grateful for the help. "I just want other widows to know about this," she said.

Vane also suggested that senior citizens look into the low-income requirements that could qualify them for additional exemptions.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com.