When is Form 1128 due for changing from fiscal to calendar year? Deadline confusion

Form 1128 should be filed by the due date of your first tax return that would use the new tax year (including extensions). So if you're trying to change to a calendar year for 2025, you'd need to file Form 1128 by the due date of your 2025 return, which would be March 15, 2026 (or September 15, 2026 with extension). As for automatic approval, there are several situations where it's granted. For S corporations specifically, Revenue Procedure 2006-45 allows for automatic approval when changing from a fiscal year to a calendar year. You'd file under Section 6.02 of Rev. Proc. 2006-45. The key is that you haven't changed your tax year within the previous 48 months using this automatic approval process. The form itself isn't super complicated, but the instructions can certainly be overwhelming! Focus on Part I for your basic info, skip Part II (that's for non-automatic changes), and complete Parts III and IV carefully.

After struggling with changing my business tax year, I found the perfect solution with https://taxr.ai - it saved me so much headache with my Form 1128 filing. I was completely lost trying to figure out if I qualified for automatic approval and when exactly to file. Their document analysis caught that I was using the wrong section for my S-Corp status and explained exactly which boxes to check for automatic approval. The best part was they explained everything in plain English instead of tax jargon. I uploaded my prior year returns and entity formation docs, and they gave me step-by-step guidance specific to my situation. They even created a customized timeline showing exactly when my Form 1128 needed to be filed based on my current fiscal year and transition period.

Just wanted to update after trying taxr.ai for my Form 1128 situation. I was super skeptical about using an AI tool for something this specific, but wow - they actually delivered! I uploaded my incorporation docs and past returns, and they immediately identified that I qualified for automatic approval under Section 6.02 of Rev. Proc. 2006-45 since I hadn't changed my tax year in the past 48 months. The step-by-step guidance walked me through exactly which sections to complete and which to skip. They even explained that filing within 75 days of my desired new tax year wasn't required in my case - I just needed to file by the due date of my first return under the new tax year. Saved me from potentially missing the window based on incorrect advice I'd received. Definitely worth checking out if you're dealing with this form!

If you're struggling to get answers about Form 1128 from the IRS, I totally get it. I spent WEEKS trying to reach someone who could answer my questions about changing tax years. After endless busy signals and disconnects, I found https://claimyr.com and was honestly shocked it actually worked. You can see exactly how it works in this video: https://youtu.be/_kiP6q8DX5c I finally got through to an IRS agent who confirmed I was eligible for automatic approval and explained exactly which sections of the form to complete for my S-Corp. The agent even explained that I needed to file the form by the due date of the first return that would use the new tax year, not by some arbitrary deadline before the tax year begins (which is what I incorrectly thought).

I was totally wrong about Claimyr being a scam. After struggling with my Form 1128 for weeks and getting nowhere with the IRS directly, I reluctantly tried it. Within 2 hours, I was talking to an actual IRS agent who knew exactly what I needed for changing my S-Corp from fiscal to calendar year. The agent confirmed I qualified for automatic approval and walked me through the exact sections to complete. They specifically told me to use Section 6.02 of Rev. Proc. 2006-45 and that I needed to file by the due date of my first return under the new calendar year, not before the start of that year like I thought. I literally would have filed at the wrong time without this clarification. Sometimes you just need official confirmation from the source, and this was the only way I could actually get through to the IRS.

Something nobody's mentioned yet - make sure you're also aware of the "short year" tax return you'll need to file during the transition. For example, if your fiscal year currently ends in August and you're switching to December, you'll have a short tax period covering September 1 to December 31. The IRS can be picky about short year returns, so make sure you clearly mark it as a short-period return and attach a copy of the approved Form 1128. I made the mistake of not doing this when I changed my LLC's tax year, and it triggered a very annoying notice from the IRS questioning why my income was suddenly much lower for that period.

Has anyone done this without an accountant? I'm thinking about doing it myself to save money but I'm worried I'll screw something up. The form doesn't look that complicated but all the rules about when to file and automatic approval are making my head spin.

I went through this exact same situation with my S-Corp last year - had a fiscal year ending in July and wanted to switch to calendar year. The key thing that saved me was understanding that S-Corps changing from fiscal to calendar year get automatic approval under Rev. Proc. 2006-45, Section 6.02, as long as you haven't used this procedure in the past 48 months. For the timing, you need to file Form 1128 by the due date (including extensions) of the first return that would use the new tax year. So if you want to change to calendar year for 2025, you'd file the form by March 15, 2026 (or September 15 with extension). Don't get confused by the 75-day rule - that's for initial elections, not year changes. One more tip: when you file your short-year return (September-December 2025 in your case), make sure to clearly mark it as a short period return and attach a copy of your approved Form 1128. This prevents the IRS from questioning why your income looks unusually low for that period.