1. Average SSDI Payment in Illinois

• As of 2025, the average monthly SSDI payment in Illinois is approximately $1,495.
• This amount is in line with the national average and reflects the typical benefit most recipients receive based on their work history and earnings contributions over their lifetime.
• Payments can vary significantly depending on how much you paid into Social Security during your working years. Some recipients may receive as little as $800 per month, while others may receive over $1,800 per month

2. Maximum SSDI Payment

• The maximum SSDI benefit for 2025 is $4,018 per month.
• To receive this maximum amount, an individual must have earned the maximum taxable income under Social Security for at least 35 years.
• Very few claimants receive the maximum; most receive payments closer to the average unless they have had consistently high earnings throughout their career.

3. How SSDI Payments Are Calculated

SSDI payments are determined using your Primary Insurance Amount (PIA). This is calculated based on:

• Your average indexed monthly earnings (AIME) during your 35 highest-earning years
• A formula applied by the SSA to determine your benefit amount

Payments are not based on state residency, meaning Illinois uses the same calculation process as every other state, though cost of living and state-specific expenses may affect how far your payment stretches.

4. Supplemental Security Income (SSI) Top-Ups

If your SSDI payment is low and you have limited financial resources, you may qualify for Supplemental Security Income (SSI) to supplement your income:

• For 2025, the maximum federal SSI payment is $967 per month for an individual.
• Some Illinois residents may qualify for a state SSI supplement in addition to the federal amount, depending on income and living arrangements.

5. Factors That Affect Your Monthly SSDI Payment

• Your lifetime earnings: Higher lifetime taxable earnings mean higher SSDI benefits
• Other benefits received: Certain pensions or workers’ compensation payments can reduce your SSDI amount
• Dependent benefits: Eligible dependents, such as children or a spouse, can receive additional benefits based on your SSDI record, increasing total household income

6. Annual Cost-of-Living Adjustments (COLA)

Each year, SSDI benefits are adjusted to keep up with inflation:

• For 2025, the COLA increase was approximately 2.5%, slightly increasing monthly payments from 2024 amounts
• Future COLA increases ensure that SSDI benefits maintain purchasing power despite rising living costs