This page provides general legal information and calculation tools, not legal advice. DocketMath is not a law firm and does not provide legal representation, and using this site does not create an attorney-client relationship. Laws change and exceptions apply, so deadlines and amounts specific to your situation should be confirmed with a licensed attorney in your jurisdiction.

Payment Plan Math in Illinois

Under Illinois law, the maximum interest rate on a written payment plan agreement is set at 9% per year, as specified by 815 ILCS 205/2. This rate applies unless the parties agree otherwise in writing, but the statute caps the rate for most consumer credit transactions. The calculation is straightforward: interest accrues on the unpaid principal balance at the annual rate of 9%, divided by the number of payment periods. The worked example below illustrates how this formula applies to a typical installment schedule. For an estimate tailored to your specific balance and payment terms, use the DocketMath calculator, which applies the statutory rate directly from the official source.

Governing authority

In Illinois, the payment plan math rule is set by 815 ILCS 205/2. The verified packet cites 815 ILCS 205/2 (https://www.ilga.gov/legislation/ilcs/fulltext.asp?DocName=081502050K2).

Illinois payment plan math: the verified value is 9% under 815 ILCS 205/2. The verified packet cites 815 ILCS 205/2 (https://www.ilga.gov/legislation/ilcs/fulltext.asp?DocName=081502050K2).

Estimate your own result: every situation has exceptions that can change the outcome. Use the payment plan math calculator to estimate your specific figure.

This page provides general legal information and calculation tools, not legal advice. DocketMath is not a law firm and does not provide legal representation, and using this site does not create an attorney-client relationship. Laws change and exceptions apply, so deadlines and amounts specific to your situation should be confirmed with a licensed attorney in your jurisdiction.