According to a press release from Cook County Treasurer Maria Pappas, as many as 31,000 senior citizens could save a total of $43 million on their property tax bills due August 1, 2018, by applying for exemptions they received in the previous year.

Those homeowners received the Senior Citizen Homestead Exemption last year but have not reapplied, according to an estimate by the Treasurer's Office. Of those seniors, roughly 21,000 received the Senior Freeze Exemption last year but also have not reapplied, Pappas added.

To verify tax exemptions going back four years, visit cookcountytreasurer.com and:

• Select the purple box, which says "Your Property Tax Overview"
• Enter your address or Property Index Number (PIN)
• Check the results under "Have You Received Your Exemptions in These Tax Years?" 

State law requires that senior citizens reapply every year for these exemptions, which are available to homeowners who are 65 years of age or older. The Senior Freeze, which prevents increases in the taxable value of a home, is limited to seniors with annual household incomes of $65,000 or less. Some of the homes may no longer be eligible for the exemptions.

Applications for tax exemptions are available from the Cook County Assessor's Office. If the Assessor's Office grants the application, it will issue an adjusted bill for the Second Installment of Tax Year 2017, due August 1, 2018.