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IL-1040-V and IL-1040-ES Alert: If paying by a paper check, make sure that the voucher (IL-1040-V and IL-1040-ES) sent with the payment shows the correct scan line. The voucher should display the full Social Security number. The scan line at the bottom of the voucher should not contain any asterisks or other symbols. The full Social Security number information in the scan line helps the payment be quickly applied to the correct account – avoiding errors and delays.

Note: The individual income tax rate decreased on January 1, 2015 to 3.75%. The IL-700-T, Illinois Withholding Tax Tables for 2015, is now available on our website at, which enables employers to determine how much tax to withhold from employee paychecks under the new rate.

For more information, see:

  • FY 2015-09 - Illinois Income Tax Rate Decrease Informational Bulletin
  • FY 2015-08 - Withholding Tax Changes Informational Bulletin

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