Wisconsin’s Change to 15-Digit Withholding Tax Account Number

The Wisconsin Department of Revenue announced that beginning September 2, 2008 all newly registered employers will be assigned a 15-digit Wisconsin Tax Account Number (WTN) (formatted as 036-9999999999-09).  All existing employers with a 7-digit (formatted as 999999-9) or a 6-digit (formatted as 999999) Wisconsin Employer’s Identification Number (WEIN) will be replaced by their existing 15-digit WTN as the primary identifier for their Withholding Tax account.

The Department will continue to accept any previously issued 7-digit WEIN and there will be no negative processing impact.  The Department expects to have all taxpayers using the15-digit WTN exclusively by the beginning of Tax Year 2009.  The WTN will be required with the 2008 Form WT-7, Employers Annual Reconciliation filing, due by January 31, 2009.  

Frequently Asked Questions

How do I know if I'm affected?

You may be affected if you currently withhold Wisconsin income taxes from employee’s wages, have a valid Wisconsin Employer Identification Number or a valid Wisconsin Tax Account Number.

What documents can I refer to that may contain my 15-digit WTN?

Refer to your Registration Certificate or the Business Tax Registration greeting letter.

Who can I contact at the Department to find out what is my 15-digit WTN?

You may contact the Department via

• Phone: 608-266-2776
• Fax:  608-267-1030
• Email: sales10@revenue.wi.gov
• Mail: Wisconsin Department of Revenue, Customer Assistance Bureau, P.O. Box 8949, Madison, WI 53708-8949

What steps do I need to take next?

You will need to download and install Payroll Update #20812 as soon as it is released.

For more information on how to download and install a Payroll Update, click on the Help menu, select User’s Guide from the drop down list, click on the Index tab, and then type “Updating” in first field.  Help is provided for both downloading and installing Payroll Updates.

What steps should I take after installing Payroll Update #20814?

To modify the account number reflected in your company file, please take the following steps:

1.      Refer to Registration Certificate, Business Tax Registration greeting letter or call the Department for your 15-digit WTN.

a.       From the List drop down menu, select Payroll Items.

b.      Select WI – Withholding.

c.       Click Next to get to the Agency for employee-paid liability screen.

d.      Enter your 15-digit Wisconsin Tax Account No. in the Enter the number that identifies you to agency box.

e.       Click Next and then click Finish