I extended my US return by making an extension payment electronically, per the following from Form 4868 instructions:
You don’t need to file Form 4868 if you make a payment using our electronic payment options. The IRS will automatically process an extension of time to file when you pay part or all of your estimated income tax electronically.
Wisconsin accepts US extensions, but wants a copy of Form 4868 (none exists), or a statement that you are using the US automatic 6 month extension. I checked the box in the Wisconsin input that says I have a US extension, but I see nothing in the filing forms that is the statement Wisconsin requires. I also see no way to add a statement to the WI return. If I paper file Wisconsin, I could create a statement and include it, but I find it hard to believe that is what Intuit intends.
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