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Do you know your PIN? Understanding Your Cook County Property Index Number

What is a PIN?

PIN stands for Property Index Number. Sometimes it’s also referred to as a Parcel Identification Number.

A PIN is a 14-digit code that functions as a unique identifier for a parcel of land. All types of properties have PINs, including:

  • Single family homes
  • Vacant lots
  • Apartment buildings
  • Individual parking spaces within a parking lot
  • Common areas in community associations

If you look at a county’s real estate tax maps, each piece of land is labeled with a PIN.

Is my PIN random numbers?

The 14 digits are not random. A PIN is a structure and each of its segments have meaning.

  • The first two digits in the sequence are the area number.
  • The second two are the subarea number.
  • The next three PIN digits are the block number.
  • The following three digits are the parcel number
  • The remaining four PIN digits are the unit number.

If the unit number is four zeros, this indicates a building that is not a condominium or leasehold. If there are any other numbers in the last four digits, then the PIN refers to a unit within a condominium or leasehold.

How do I find my PIN?

The easiest way to find a PIN is to check your deed or tax bill. Some deeds only contain a legal description.

You can also use the Cook County Assessor’s website to find your PIN by entering your address. However, the search does not always return a precise match.

How often do PINs change?

A parcel’s PIN will change when its legal description is revised. For example, if a property has been divided in half then the two halves will be assigned independent PINs.

What do I do if my PIN is the same as my neighbor’s PIN?

In brand new developments, issues with duplicate PINs sometimes occur. If this happens, contact the Cook County Treasurer’s Office to begin the process of paying by legal description rather than PIN.

It’s best to get this sorted out immediately, especially if other owners who share your PIN are delinquent on their property taxes.

What do I need my PIN for?  

If you have recently purchased a home and the property taxes are being paid from your escrow, you will want to be certain that your mortgage company is making complete, prompt, and accurate payments. Your PIN can be used to verify that the payments are being made and that they are applying to the property you own.

PINs are used for property tax purposes such as assessments and tax collections. It is crucial to have the correct PIN on the tax bill that you pay. If you pay the amount of your bill for a PIN other than the one that corresponds to your property, your actual taxes will still be delinquent.

Some property owners may not realize that their property lands directly between two parcels and they are responsible for paying taxes on both. Why? It’s possible that only one PIN was mentioned when they purchased their home or unit. An attorney can assist with PIN verification matters.

Finally, being familiar with your PIN and the PINs of neighboring properties can be important if you would like to appeal your taxes. If you want to lower your assessment based on lack of uniformity, you can submit the PINs of similar properties and other supporting documentation to the Cook County Board of Review.

Property taxes unappealing? We can help!

Appealing your property taxes is one way to ensure that the amount you pay is fair whether you live in the north/northwest suburbs, south/southwest suburbs, or in the City of Chicago.

At present, Illinois is second only to New Jersey with the highest effective property tax rates in the United States. A 2020 study found that some Chicago area homeowners pay twice the national average in property taxes for a similarly valued home. Moreover, property tax hikes are slated for 2021.

Appeal.Tax can prepare your property tax appeal and handle it from start to finish. We understand local appeal procedures to help homeowners avoid being overburdened with property taxes.

Appeal.Tax has no fee unless a reduction is obtained. And we only charge a small portion of the overall tax savings secured. 

Since 2015, we’ve saved Illinois property owners over $100 million in reduced property taxes.

Contact Appeal.Tax today to discuss your Association, residential, or commercial property tax appeal. Tax Attorney Timothy Jacobs can be reached at 847-777-7270 or