Base Period Defined

• The state of Illinois states that its base period for calculating unemployment benefits is "a period of one year and does not include the most recent quarter (most recent three months)." In other words, the base period is the first four of the last five completed calendar quarters that precede your claim. For example, if you lose your job in May 2011, your base period will be the one-year period from January 1, 2010, to December 31, 2010. If you file for unemployment in July 2011, your base period is April 1, 2010, to March 31, 2011.
  
  

Alternate Base Period

• Illinois is one of the states that recognizes an alternate base period for workers whose standard base period income does not qualify them for benefits. The alternate base period is the last four of the last five calendar quarters before you make your benefits application. In addition, according to Nolo Press, even if your standard base period does qualify you to collect, you are free to ask the Illinois Department of Employment Security to use the alternate base period if using it will increase your weekly benefit amount. As an example, if you file for unemployment in May 2011, your alternate base period will be April 1, 2010, to March 31, 2011.
  
  

Base Period Minimum

• In Illinois, you must have earned at least $1,600 during your base period and at least $440 of that must have been earned outside your highest-earning quarter. So, if you earn $2,400 in one quarter and $300 total in the other three quarters, you will not be eligible for unemployment benefits. On the other hand, if you make $1,200 in one quarter and $500 total during the other three quarters, you will pass the earnings test.
  
  

Reason for Separation

• In most states, the general rule is that you must have lost your job through no fault of your own to be eligible for unemployment. So, when an assignment ends, even if sooner than the expected end date, you can apply for benefits. In Illinois, any employee who is dismissed for stealing or committing a felony is automatically disqualified from eligibility. Moreover, if you quit a job due to sexual harassment or for health reasons, you may still be able to collect benefits. Furthermore, if you leave a temp job to take another job -- such as a permanent job -- and that new job fails to materialize, you may be eligible for unemployment.
  
  

Availability for Work

• As in any other state, to be eligible for benefits, you have to be able and available to work. In addition, you must be actively seeking employment. For example, if your temporary assignment ends and you tell an agency you are working for that you are unavailable for a few months, you will not be eligible to collect. To cover yourself, it is a good idea to contact your temporary agency weekly to communicate your availability.
  
  In addition, if you are offered work that is suitable to your skill set at your usual pay rate and you refuse the job, you will make yourself ineligible for benefits.