Wisconsin State Business & Corporate Tax Extension

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Requirements for Filing a Business Tax Extension in the State of Wisconsin

Wisconsin corporation tax returns are due by the 15th day of the 3rd month after the end of the tax year. For calendar year filers, this date is March 15. If you cannot file on time, you can get a Wisconsin tax extension.

If you have filed an IRS business tax extension online or mailed in (IRS Form 7004), you will automatically receive a Wisconsin business extension. This will extend your Wisconsin filing deadline by 7 months to 30 days beyond the Federally extended due date. There is no form that you need to file with the State to obtain a Wisconsin business tax extension and you do not need to send in a copy of your federal extension, but make sure to attach a copy of your approved Federal business tax extension to your Wisconsin tax return when it’s filed.

If you don’t have a Federal extension, you can obtain a Wisconsin-only tax extension of 7 months OR until the original deadline of the corresponding Federal corporation return, whichever date is later.

An extension of time to file is NOT an extension of time to pay. Your Wisconsin tax must be paid by the original due date (March 15) or interest and penalties will be charged. To make a Wisconsin extension payment, use Form Corp-ES (Wisconsin Corporation Estimated Tax Voucher).

NOTE: Wisconsin partnership tax returns are due by the 15th day of the 4th month after the end of the tax year (April 15 for calendar year filers). A partnership can obtain a 5-month Wisconsin tax extension. If the partnership has a valid Federal extension (IRS Form 7004), a Wisconsin extension will be automatically granted. Otherwise, partnerships can request a Wisconsin tax extension by completing a copy of Federal Form 7004 or a written statement indicating which Federal extension provision you are utilizing, and attaching that to their Wisconsin return when it’s filed.

For more information on Wisconsin corporation tax returns, please visit the Wisconsin Department of Revenue website at: www.revenue.wi.gov

What Business Extension Forms Are Required by the State of Wisconsin ?

Form Corp-ES (Wisconsin Corporation Estimated Tax Voucher): https://www.revenue.wi.gov/TaxForms2017through2019/2018-FormCorpES.pdf

Form Corp-ES Instructions: https://www.revenue.wi.gov/TaxForms2017through2019/2018-FormCorp-ES-inst.pdf 

Mail with payment to the following address:

Wisconsin Department of Revenue
P.O. Box 930208
Milwaukee, WI  53293-0208

You may also make Wisconsin business tax extension and estimated tax payements online at: https://tap.revenue.wi.gov/mta/_/ 


Corporation Franchise / Income Tax Assistance
P.O. Box 8906
Madison, WI 53708-8906

Phone: (608) 266-2772

Fax: (608) 267-0834

Email any questions to: [email protected]

Mailing Business Tax Extension Forms?

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The rules and regulations for business tax extensions are different in every state. Some states will automatically grant you a state tax extension if you obtain a valid Federal extension — but other states require a separate state-specific application. For state-by-state information about filing tax extensions, please visit our State Tax Extensions center.

If your company maintains financial books/records, you can determine your current tax liability if you multiply your taxable income by the applicable tax rate. Many people simply use their numbers from last year’s tax return (as long as your tax situation is relatively similar). Remember to reduce your current tax balance by the amount of tax that was withheld (or paid via estimated tax payments), if any, during the year.

Yes. You can get more time to file for an estate or trust by submitting IRS Form 7004 for a business tax extension. An extension will give you 5 extra months to file Form 1041 (U.S. Income Tax Return for Estates and Trusts). During TaxExtension.com’s online application process, you will have the option of choosing “Estate” or “Trust” for your business entity type.

It depends on what type of LLC you have. For Federal income tax purposes, a multi-member LLC is classified as a “partnership” by default (unless it specifically elects to be treated as a corporation). A multi-member LLC classified as a partnership should request a business tax extension (IRS Form 7004) to get 5 extra months to file. A multi-member LLC classified as a corporation should also request a business tax extension, which provides 6 extra months to file a corporation return. On the other hand, a single-member LLC is classified as a “disregarded entity” by default (unless it specifically elects to be treated as a corporation). When a single-member LLC is treated as a disregarded entity, that means its activities are reported on the owner’s individual income tax return (Form 1040). So if you have a single-member LLC, you only need one (1) personal tax extension (IRS Form 4868) to cover yourself and your business, which gives you 6 extra months to file your return.

Independent contractors (Form 1099), sole proprietors (Form 1040 Schedule C), and single-member LLCs that report their business activities on their personal tax return (IRS Form 1040) should request a personal tax extension — not a business extension. For these taxpayers, a personal extension (IRS Form 4868) will cover both themselves and their business. If you have a different type of business, such as a partnership or S-corporation, you should file IRS Form 7004 for a business tax extension.

An IRS tax extension will give a business 5 or 6 extra months (depending on the type of business entity) to file its Federal income tax return. A business tax extension grants 5 more months to file: Form 1041, Form 1065, and Form 8804. A business tax extension grants 6 more months to file: Form 706-GS(D), Form 706-GS(T), Form 1041 (bankruptcy estate only), Form 1041-N, Form 1041-QFT, Form 1042, Form 1065-B, Form 1066, Form 1120, Form 1120-C, Form 1120-F, Form 1120-FSC, Form 1120-H, Form 1120-L, Form 1120-ND, Form 1120-ND (section 4951 taxes), Form 1120-PC, Form 1120-POL, Form 1120-REIT, Form 1120-RIC, Form 1120S, Form 1120-SF, Form 3520-A, Form 8612, Form 8613, Form 8725, Form 8831, Form 8876, Form 8924, and Form 8928. Our easy-to-use online application makes it easy for you to select the correct business entity type. If you are unsure which business tax return is required for your business, TaxExtension.com will help you figure it out.

Most partnerships and multi-member LLCs are required to file a separate income tax return, which means you will need a business extension to cover your business tax return, plus a personal extension to cover your personal tax return. On the other hand, a single-member LLC is classified as a “disregarded entity” (or “pass-through entity”), which means the business activities are reported on the owner’s personal tax return. In that case, you would only need a personal tax extension to cover both you and your business.

If you file a separate tax return for your business and you’re required to provide the business’ EIN (employer identification number) on the return, you should also provide the EIN on your tax extension request. Note that most businesses are required to obtain an EIN, which the IRS uses to identify a business entity. However, if you have a single-member LLC — which is considered a “pass-through entity” (or “disregarded entity”) — you should use your SSN (Social Security Number) instead of an EIN. Pass-through entities are reported as part of the owner’s personal tax return, which means you only need one (1) personal tax extension (IRS Form 4868) to cover both yourself and your business.

Corporations are granted a 6-month tax extension, which moves their filing deadline from March 15 to September 15. Trusts, certain estates, most partnerships, and some multi-member LLCs are granted a 5-month tax extension, which moves their filing deadline from April 15 to September 15.

In most cases, you will hear back from the IRS within 24 hours of submitting your business tax extension online. However, it’s important to note that IRS response times will be longer than normal on the last day of filing (March 15 and April 15). As soon as your business extension is approved by the IRS, you will receive an email from TaxExtension.com with the details of your extension, including your official IRS confirmation number.