If you own a home or property in Chicago, it's probably worth more -- maybe two or three times more -- than it was three years ago, according to the Cook County assessor. And you'll be taxed accordingly.

The Civic Federation of Chicago calculates an average 36 percent hike in every tax bill -- or $829 more a year, unless state legislators renew a homeowners' protection bill that would drop the average hike down to about $255.

The assessor's office finished its once-every-three-years assessment of property in Chicago, and just about every corner of the city is seeing a whopping increase in assessed home values.

In theory, that's great news if you're selling your property and could expect a big profit. In practice, try telling that to homeowners who have had their homes on the market for a year since real estate sales plummeted back to Earth.

But for those staying put, it means tax bills are likely to go up. A 200 percent hike in assessed value will not necessarily translate to triple taxes because just about everyone else's bill in the city is going up, too, so the increase will be spread out.

But the Cook County suburbs are not being re-assessed, so city residents will pay a proportionately higher share to taxing agencies such as county government and the forest preserve that tax countywide. That's payback for the suburbs paying a disproportionate share over the last two years.

Helen Quaites saw the assessed value on her Washington Park home jump from $51,000 to $180,000. Earnest Horton saw the assessed value of his Fuller Park six-flat jump from $54,000 to $238,000.

"You don't have any choice -- you pay it or you have to move," said Leonard Gilbert, whose taxes on his Rogers Park home are jumping from $4,604 to $6,513 unless the protection bill passes. "I pay more in taxes now than on my mortgage."

MADIGAN BLOCKING CAP?

City and suburban homeowners have been shielded from big tax hikes for three years by the so-called 7 percent tax cap or "Expanded Homestead Exemption," but that's set to expire this year. Mayor Daley, County Assessor Jim Houlihan, Gov. Blagojevich and state Sen. Emil Jones support renewing it.

House Speaker Michael Madigan's spokesman says he is for the bill and voted for it last time around, but many of the bill's backers say Madigan is the force blocking the bill in Springfield. Madigan's office sent out a study ordered by his office showing 52 percent of property owners were not helped by the cap.

The relief the cap gives to homeowners whose taxes would otherwise skyrocket comes at the expense of owners of business or multi-unit apartment property. The Madigan-cited study completed by the state revenue department says the pain of increased property taxes -- some $323 million worth -- is passed from homeowners to commercial properties ($135 million); apartment building owners ($25 million); other homeowners ($79 million) and "others" ($84 million).

But a Civic Federation study released Monday finds that rather than facing a property tax hike, owners of commercial, industrial and apartment property will see their tax bills go down whether or not the cap is renewed. That's because home values are rising so much faster than other properties.

The average Chicago apartment owner's tax bill will drop $1,051 a year with the cap; $1,643 without it, the study says. Commercial property owners will see theirs drop $216 with the cap; $488 without.

apallasch@suntimes.com

FIGURE YOUR TAXES IN FOUR STEPS:

The easiest way to figure your taxes is to look at your most recent notice from the county assessor's office. It lists your home's estimated market value, a smaller number called the "assessed value" and your projected taxes. If you don't have it handy, you can plug your address into the assessor's Web site and get the first two numbers. The market value is probably less than what your home would fetch on the market. The assessor's office errs on the low side.

1. Starting with your home's estimated market value, multiply that number by .16. (Residential property is assessed at 16 percent of its value in Cook County.)

2. Then multiply that number by 2.732. That's the "equalizer" adopted by the state to correct for the fact that Cook County assesses at 16 percent for residential property, a different rate than other local governments.

3. Deduct from that number any exemptions such as the homeowner's exemption of $5,000 and/or the senior exemption of $3,000.

4. Multiply that number by the tax rate paid by Chicago residents of 4.791 percent. Those will be the taxes you pay in two installments next year.

But there are a lot of exceptions. Suburban tax rates will vary school district by school district and from one municipality to the next. If legislators renew the "7 percent cap," the homeowner's exemption will rise all the way up to $20,000 for qualifying homeowners.

For more information, visit www.suntimes.com.