Illinios Information IL Farm Returns - March 1st IL Corporation Returns - March 15th Illinois Returns - April 15th Illinois Estimates Due - Apr/Jul/Oct/Jan Illinois Quarterly Reports - Apr/Jul/Oct/Jan Illinois Circuit Breaker Application - 31st Dec. Each Year ILLINOIS TAXPAYER ASSISTANCE.............1-800-732-8866 TDD...........................................................1-800-544-5304 BUSINESS HOT LINE.................................1-217-524-4772 CIRCUIT BREAKER/PHARM.......................1-800-624-2459 FORMS ORDER LINE................................1-800-356-6302 ILLINOIS TAX FAX......................................1-217-785-3400 WEBSITE..................................................www.ILtax.com [www.ILtax.com]   Compton Accounting ~ 309-484-8888 ~ www.comptonaccounting.com ~ Altona, Illinois