
Quoting
820 ILCS 405/601(A) - Voluntary leaving
A. An individual shall be ineligible for benefits for the week in which he has left work voluntarily without good cause attributable to the employing unit and, thereafter, until he has become reemployed and has had earnings equal to or in excess of his current weekly benefit amount in each of four calendar weeks which are either for services in employment, or have been or will be reported pursuant to the provisions of the Federal Insurance Contributions Act by each employing unit for which such services are performed and which submits a statement certifying to that fact.