@nv1975 wrote:
how do I do that in Turbotax 2018? I have Turbotax business 2018 premier.
I hope you meant to write that you have TurboTax Business (there is no such product as Business premier). I have to presume you do or else you would not have been able to prepare an 1120 for a C corporation.
Regardless, you can late file a Form 2553 (link to form below) and hope that the IRS will accept your excuse for filing late, but you should absolutely follow the IRS instructions you received to the letter.
Form 2553: https://www.irs.gov/pub/irs-pdf/f2553.pdf
[note that you can prepare the form in TurboTax Business but you have to print it out and mail it, anyway]
You can also not simply "amend with 1120" in such a manner that you wind up with an S corporation return. Rather, in TurboTax Business you have to start a completely new return after selecting S Corporation (Form 1120S) as the type of return you want to file.
Although the IRS already is aware that you filed the wrong type of return. You might also want to consider filing an amended 1120 to essentially "zero out" the original return. Again, however, you should follow IRS instructions and, if in doubt, contact them directly and inquire as to exactly how they would like you to handle the matter.
Finally, you should seriously consider consulting with a tax professional for this entire matter so that it gets resolved correctly.
