The Illinois Department of Employment Security, or IDES, is responsible for administering the state's unemployment insurance program. The program assists eligible out-of-work Illinois residents with a weekly benefit while they are seeking full-time employment. In Illinois, employers, not employees, pay into the unemployment insurance program. Thus, unemployment insurance claimants receive benefits only for what the IDES defines as insured work, which is work performed for employers required to pay unemployment insurance taxes.

Establishing Eligibility

To be eligible for unemployment benefits, claimants must have earned at least $1,600 or more for performing insured work during their base period. They must have also earned at least $440 in the two lowest-paying calendar quarters in their base period. The date that claimants file for unemployment starts their benefit year, in which they may receive benefits for up to 26 weeks. All numbers mentioned here are valid as of March 2015.

Determining a Claimant's Base Period

The IDES starts determining unemployment benefits for claimants by figuring their base period, which is the first four calendar quarters in the last five complete calendar quarters that claimants worked prior to their benefit year. A calendar quarter is three months, of which there are four in a year: January through March, April through June, July through September and October through December. For example, if you began your benefit year in February 2015, your base period would be from October 1, 2013 to September 30, 2014.

Figuring Weekly Benefits

The IDES figures claimants' total unemployment benefits as being 47 percent of the earnings that they made in their two highest paid calendar quarters. To calculate their weekly benefit, IDES multiplies their total benefits by 47 percent. That figure is then divided by 26, for the maximum number of weeks that claimants can receive benefits. The weekly benefit cannot be less than the minimum benefit of $51, nor can it be higher than the maximum benefit of $426. For example, suppose you earned $25,000 in your two highest calendar quarters. Forty-seven percent of that amount is $11,750, which divided by 26 weeks is $451.92 per week. Because it is greater than the maximum benefit allowed, you receive $426 per week.

Claiming a Dependent's Allowance

In Illinois, claimants can receive an allowance for either their dependent children or nonworking spouse. In 2015, the allowance rate is 17 percent for each dependent child and 7 percent for a spouse. The dependent's allowance is added to the claimants' weekly benefit. The IDES places a limit on the total combined amount of benefit and allowance. In 2015, the maximum amount for claimants with dependent children is $580 per week, and with a spouse, $507 per week.

Extending Weekly Benefits

During periods of very low employment rates, the U.S. Congress may create legislation to extend unemployment insurance benefits for several more weeks. In 2008, Congress passed a law that established the Emergency Unemployment Compensation program, which provided for qualified claimants in Illinois and the other 49 states to receive additional weekly benefits if they had not found a job after their regular benefits ran out. However, this program expired in 2014.