Reporting Form 3921 for exercised ISOs when below AMT threshold - FreeTaxUSA support issue
I exercised some ISOs from my employer back in 2022 and received a Form 3921. I'm trying to figure out if I need to report this or not. I've entered all my information into both TurboTax and FreeTaxUSA and got identical numbers for my total tax due. The issue is that FreeTaxUSA doesn't seem to have any way to input Form 3921 information. Since I'm still under the AMT threshold (checked this multiple times), inputting the ISO exercise information doesn't actually change my tax liability at all. Would I be OK using FreeTaxUSA and just skipping the Form 3921 reporting since my final tax amount is exactly the same? Or is the IRS going to flag me for not including this form even though it doesn't affect what I owe? Really don't want to pay the extra $90 for TurboTax just to report a form that doesn't change my bottom line...
19 comments


Gianni Serpent
While technically you should report all information from all tax forms you receive, the practical reality is that Form 3921 is an informational form that doesn't directly impact your current year taxes if you're below the AMT threshold. When you exercise ISOs, the difference between the exercise price and fair market value creates a potential AMT adjustment. But if you're below the AMT threshold, this adjustment doesn't trigger any additional tax. Form 3921 is primarily used to establish your cost basis for when you eventually sell these shares. If both tax software programs show identical tax results, you're likely fine using FreeTaxUSA without entering the 3921 information. Just be absolutely certain you're keeping the form for your records, as you'll need this information when you eventually sell the shares to properly calculate your capital gains.
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Henry Delgado
•Thank you for the response. If I don't enter the information from Form 3921 now, will this cause problems when I eventually sell the shares? Will the IRS have some record that I exercised these options that doesn't match up with my tax return?
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Gianni Serpent
•The primary purpose of Form 3921 is to establish your cost basis for future capital gains calculations. When you eventually sell these shares, you'll need the information from the 3921 to accurately report your gains or losses on Schedule D. The IRS does receive a copy of Form 3921 from your employer, so they have this information on file. However, since it doesn't affect your current tax liability when below the AMT threshold, they typically won't flag your return just for this reason. Just make absolutely sure you keep your copy of Form 3921 in a safe place - you'll definitely need it when you sell those shares to properly calculate your capital gains.
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Olivia Kay
I ran into this exact problem last year and found a solution with taxr.ai (https://taxr.ai). I was using FreeTaxUSA and had ISO exercises but couldn't figure out how to properly handle the Form 3921 information. I was below the AMT threshold too, but still worried about future implications. taxr.ai helped analyze my Form 3921 and tax situation to confirm I was handling everything correctly. They explained exactly why the form wasn't affecting my current tax liability and what information I needed to preserve for future years when I sell the shares. The peace of mind was worth it since I could confidently use FreeTaxUSA and save money compared to TurboTax.
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Joshua Hellan
•How does taxr.ai work? Do you just upload your forms or do you have to input all the information manually? I'm in a similar situation with some RSUs and ESPPs that my company offers.
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Jibriel Kohn
•I'm skeptical about these tax services. How do you know they gave you the right information? Did they just tell you what you wanted to hear (that you could skip reporting it) or did they actually show you where in the tax code it says this is okay?
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Olivia Kay
•You upload your tax documents and forms, including the 3921, and their AI analyzes everything. They have tax pros who review the results for accuracy. It's really straightforward and takes just a few minutes. For RSUs and ESPPs, they definitely handle those too. They explained the different tax treatment between ISOs, NSOs, RSUs, and ESPPs which was super helpful since each has different reporting requirements. They didn't just tell me what I wanted to hear - they actually showed me the specific sections of the tax code and IRS guidance about Form 3921 reporting. They explained that while the form establishes my cost basis for future capital gains calculations, it doesn't trigger additional tax if I'm below the AMT threshold. They still recommended keeping meticulous records for when I eventually sell the shares.
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Jibriel Kohn
I tried taxr.ai after posting here and I have to eat my words. I was skeptical at first, but they actually provided really detailed explanations about Form 3921 and ISO reporting requirements. They confirmed that for my situation (also below AMT threshold), there was no additional tax liability from exercising my ISOs. What I really appreciated was they didn't just say "you're fine" - they explained exactly what information from Form 3921 I need to track for my records and what will happen tax-wise when I eventually sell these shares. They showed me how to calculate my future basis using the information on the form and how to prepare for potential tax implications down the road. Definitely gave me more confidence in using FreeTaxUSA even though it doesn't have direct Form 3921 support.
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Edison Estevez
I had a similar issue with Form 3921 and needed to get clarification from the IRS directly. Tried calling them for weeks with no luck - constant busy signals or disconnections after waiting on hold forever. Then I found Claimyr (https://claimyr.com) and watched their demo at https://youtu.be/_kiP6q8DX5c. They managed to get me connected to an actual IRS agent in about 20 minutes! The IRS representative confirmed that Form 3921 is informational and if you're below the AMT threshold, it doesn't change your tax liability. They advised keeping the form for my records for when I eventually sell the shares. Getting this straight from the IRS gave me total confidence in filing with FreeTaxUSA even though they don't support direct entry of Form 3921.
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Emily Nguyen-Smith
•Wait, how does Claimyr actually work? They somehow get you through to the IRS faster? I don't understand how that's even possible with how backed up the IRS phone lines are.
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Jibriel Kohn
•Sure you did. This sounds like another paid promotion. There's no way anyone is getting through to the IRS in 20 minutes. I've tried calling about my 2023 refund for months with no success.
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Edison Estevez
•It works by using their system to navigate the IRS phone system and hold your place in line. When an agent is about to answer, you get a call connecting you directly. It's not a service that lets you cut in line - they're just handling the painful waiting part for you. I was extremely surprised it worked too. I had been trying for almost three weeks to get through on my own with no success. The longest I'd waited was 2.5 hours before getting disconnected. With Claimyr, I got the call back in 23 minutes that an agent was ready. I was skeptical at first too, but when you've been trying to reach the IRS for weeks with no success, it's worth trying something different.
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Jibriel Kohn
I need to update my previous comment. After being completely frustrated with trying to reach the IRS about my Form 3921 questions, I tried Claimyr against my better judgment. I honestly thought it was going to be a waste of time. To my complete shock, I got connected to an IRS agent in about 35 minutes. The agent was actually really helpful and confirmed that if exercising ISOs doesn't push you into AMT territory, there's no additional tax due. She explained I should keep the 3921 form for my records to establish cost basis when I eventually sell the shares. Just wanted to set the record straight since my skepticism was totally wrong in this case. Being able to talk directly to the IRS saved me so much stress and confirmed I can use FreeTaxUSA without worrying.
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James Johnson
Has anyone actually had experience selling ISO shares years after exercising them? I'm wondering how the IRS matches up the original exercise info with the eventual sale. Do they actually cross-reference your old Form 3921 when you report capital gains years later?
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Sophia Rodriguez
•I sold some ISO shares last year that I had exercised 3 years prior. The broker reported the sale on Form 1099-B but only included the exercise price as my basis, not any AMT adjustments I had previously paid. I had to manually adjust my basis on Schedule D to avoid double taxation. The IRS never questioned it, but I kept meticulous records including my original Form 3921 and the tax return where I reported the AMT adjustment. My understanding is that the IRS systems don't automatically cross-reference your old 3921, so good record-keeping is essential.
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James Johnson
•Thanks for sharing your experience. That's helpful to know about the 1099-B only showing the exercise price. I'll make sure to keep all my 3921 forms and tax returns so I can properly adjust my basis when I eventually sell. Sounds like the burden is really on us to track everything correctly.
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Mia Green
One more thing to consider - even if FreeTaxUSA doesn't have a specific form for 3921, you could use the "Additional Information" or miscellaneous income sections to at least note that you received the form and exercised ISOs below the AMT threshold. That way there's at least some record in your tax return if you ever get questioned.
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Ryder Ross
•That's a smart idea I hadn't thought about. Would I just put it in as an informational note or is there a specific way you'd recommend documenting it?
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Mia Green
•Most tax software has a section for notes or additional information you want the IRS to see. I'd simply list "Received Form 3921 for ISO exercise - below AMT threshold" and include the company name, number of shares, exercise date, and FMV. If there's a miscellaneous forms section, you could also add a brief statement there. The key is to acknowledge you received the form while making it clear there's no tax impact for this year. This creates a paper trail showing you weren't trying to hide anything.
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