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Electronic Services

Electronic W-2 Transmittal Program

General Information

Payroll providers and employers may transmit W-2 and W-2c returns to Illinois using the Social Security Administration's EFW2 and EFW2C format.

To meet Illinois’ W-2 filing requirements, you must transmit your W-2s and W-2cs directly to us in one of the methods described on this page. The file transmission to Illinois is separate from the transmission to the Social Security Administration.

Note about third-party services: Payroll programs and services are available for purchase from third-party vendors which will automate this process for you. If you choose to submit your file through third-party software or services, you do not need to read the following technical instructions for transmission. However, choose third-party software or services carefully because some will only create the file to transmit but do not transmit it for you. In these cases, you must register and transmit the file yourself.

To electronically transmit your W-2s or W-2cs to Illinois, follow these steps.

  1. Register – Obtain your W-2 transmitter ID and test and production passwords. Click here to register as a W-2 Transmitter.  Note: If you are using a third-party service or program you may not need to register to transmit. Check with your payroll service or software program to see if it includes W-2 file transmission.
  2. Create your file to transmit. Develop the file following the Social Security Administration’s Publication No. 42-007, Specifications for Filing Forms W-2 Electronically,and the additional Illinois requirements in our Form W-2 and W-2c Electronic Transmission Guide (Important: PDF files or spreadsheet files, such as Excel, are not accepted.)
  3. Choose your method of transmitting the file to Illinois.
    1. Simple web file upload – This is the easiest free method available for transmitting W-2s and W-2cs. Simply logon to this secure online application using your web browser, enter your W-2 transmitter ID and password, browse for your W-2 file, and select the file to upload it. This method does not require any software download or programming.
    2. Write your own custom code for automated processing or run our HttpsPost utility program to transmit your file. See instructions and system requirements (download 2016 SSL certificates). Bulk filers and third-party payroll programs and services may prefer custom coding to transmit W-2s and W-2cs by interfacing directly with Illinois Department of Revenue's (IDOR) Gateway.
  4. Transmit your file. You must transmit both test and actual data.
    1. Test data – We will begin accepting test transmissions of the current year’s W-2 data on November 1. When online registration was completed, a W-2 transmitter ID, test password, and production password were provided to you. Use the test password to transmit your test file to IDOR. Any information transmitted using the test password will be treated as test data and is not considered “live” data. To obtain your test results, you must reenter the system at least 30 minutes after your transmission to retrieve the message (see “Retrieve your transmission acknowledgement” below).
    2. Actual data – Transmit your actual W-2/W-2c data with the same transmittal method used in your successful test transmission. Use the production password provided to you during registration. To obtain your transmission results, you must reenter the system at least 30 minutes after your transmission to retrieve the message (see “Retrieve your transmission acknowledgement” below).
  5. Retrieve your transmission acknowledgement* (proof of filing)
    1. Using your W-2 transmitter ID and password, log into the user-friendly Acknowledgement Inquiry Application 30 minutes after you transmit your W-2 file to see whether the file was accepted or rejected. If your file is transmitted successfully, you will see a message that it was accepted. If your file was rejected, review any errors present, correct your file, and resubmit until it is accepted. If no acknowledgement is present after 24 hours, please contact us for assistance. Your transmission acknowledgement message will be available for 60 days.
    2. If you transmit with your own custom code or the HttpsPost utility program, 30 minutes after you transmit the W-2 file, you may use the Acknowledgement Inquiry Application to retrieve a transmission acknowledgement message (see 5a above), or you may use your own custom code or the HttpsPost utility program to retrieve an acknowledgement file which contains information about whether the file was accepted or rejected. To read the content of the acknowledgement file, refer to the following file layouts.
      1. Form W-2: EFW2 Acknowledgement Format
      2. Form W-2c: EFW2C Acknowledgement Format

*Important note about proof of filing:  You must retrieve your transmission acknowledgement within 60 days. The Illinois Department of Revenue will not send the acknowledgement to you. Your filing requirements are not met until you receive an “Accepted” transmission acknowledgement from Illinois.

Your W-2 and W-2c filing requirements are not met if you send us files in any other format (Illinois does not accept PDFs or spreadsheets (such as Excel) containing W-2 or W-2c data) or filing method. Be aware that you will not receive a “Rejected” acknowledgement for files sent to us in other formats or methods. Please refer to the file specifications if you have questions about the correct file format.

Illinois does not accept any magnetic media or paper submissions. Do not send any magnetic media or paper submissions to Illinois. However, please note that you must keep these documents and information in your books and records for at least three years and submit them if we request. Only W-2 or W-2cs electronically transmitted in EFW2 and EFW2C format are accepted.

Start Date

Do not transmit 2016 W-2 data prior to January 1, 2017. Prior year W-2 or W-2c files can be transmitted at any time.

Due Date

For calendar years 2014 and forward, W-2s must be submitted to the Illinois Department of Revenue no later than February 15 of the year following the year of the withholding.

For 2017, the 2016 W-2s are due on or before February 15, 2017. Any time a due date falls on a weekend or state recognized holiday, we adjust the due date to the next business day.

Businesses that make a reasonable and good faith effort to comply with the deadline will not be penalized.

General record-keeping requirements

You must maintain employee Forms W-2, W-2c, W-2-G, 1099 series, or other withholding tax records for a period of three years from the due date or payment date, whichever is later.