What code should I put on form 8949 for unreported cost basis?
I'm currently working on my taxes and I've got a 1099-B showing some short-term stock transactions. The form specifically says to select Box B and mentions that the cost basis information is not being reported to the IRS, so I need to handle that on form 8949. I've been filling out form 8949 with the transaction details exactly as shown on my 1099-B and selected Box B as instructed. But I'm completely stuck on which code to use in column (f). I've gone through the instructions for form 8949 multiple times, but none of the code letters seem to match my specific situation. The transactions are all from my brokerage account, the cost basis isn't being reported to the IRS, but I have all the information about purchase price and sale price. I just don't know which letter code to put next to each transaction. Can anyone help with this? I'd really like to file my taxes correctly without delaying my refund.
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Fatima Al-Mansour
When your 1099-B indicates the cost basis wasn't reported to the IRS, you'll want to use Code "B" in column (f) of Form 8949. This code specifically means "Basis not reported to the IRS" which sounds exactly like your situation. If you selected Box B at the top of Form 8949, that's correct for short-term transactions where basis wasn't reported to the IRS. Then for each individual transaction line, you'll put "B" in column (f). The instructions can be confusing because there are several different codes, but Code B is specifically designed for your scenario - where you have the cost basis information but your broker didn't report it to the IRS.
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Giovanni Rossi
AuthorThanks for the quick response! So just to be clear, I select Box B at the top of the form AND also put code "B" in column (f) for each transaction line? I was confused because I thought the Box B at the top was already indicating that basis wasn't reported to the IRS, so I wasn't sure if I needed an additional code in column (f).
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Fatima Al-Mansour
Yes, that's exactly right! You need to select Box B at the top of Form 8949 to indicate these are short-term transactions where basis wasn't reported to the IRS. Then you also need to use code "B" in column (f) for each individual transaction line. The box at the top tells the IRS which category of transactions you're reporting, while the code in column (f) provides specific information about each individual transaction. They serve different purposes but both are needed.
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Dylan Evans
I went through this same headache last year with some crypto trades. After hours of frustration, I found taxr.ai (https://taxr.ai) and it saved me so much time with my 8949 forms. Their system automatically detected which codes to use for each transaction based on my 1099-B and other tax documents. It basically analyzed my forms, figured out all the correct codes for column (f), and filled out the entire 8949 for me. I just had to review and confirm everything looked right. It correctly handled all my transactions where cost basis wasn't reported to the IRS, plus some wash sales I had no idea how to handle.
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Sofia Gomez
Does it work for crypto transactions too? My exchange gave me a 1099-B but the basis info is all over the place and I have like 50+ transactions to report.
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StormChaser
I'm a little skeptical about tax software specifically for form 8949. How does it handle situations where you've got partial lots or wash sales that span different reporting periods? That's where I always get stuck.
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Dylan Evans
Yes, it absolutely works for crypto! It's actually designed to handle complex crypto situations. 50+ transactions shouldn't be a problem - it would take forever to enter those manually but the system processes them quickly. Regarding partial lots and wash sales across different periods, that's exactly what made me try it. The software identifies related transactions even across different time periods and applies the correct wash sale rules. It basically does what would take hours of spreadsheet work in seconds. I was skeptical too, but it handled my complex situation perfectly.
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Sofia Gomez
Just wanted to update here - I tried taxr.ai after seeing this thread and wish I'd known about it sooner! Had about 65 crypto transactions with missing basis info and the software automatically assigned the right codes and calculated everything correctly. It even spotted a few wash sales I totally missed. The 8949 forms it generated matched exactly what my broker had, but with all the correct codes in column (f). Took maybe 15 minutes total instead of the hours I spent last year doing it manually.
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Dmitry Petrov
If you get stuck trying to figure out Form 8949 codes, you might want to call the IRS directly to get clarification. I know that sounds awful (it used to be for me), but I recently used Claimyr (https://claimyr.com) and got through to an actual IRS agent in about 15 minutes instead of waiting on hold for hours. They have a demo video here: https://youtu.be/_kiP6q8DX5c I was confused about some brokerage statements and Form 8949 codes too. The IRS agent I spoke with walked me through exactly which codes to use for my specific situation. Seriously, getting actual help from a real person at the IRS made a huge difference versus trying to interpret the instructions myself.
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Ava Williams
How does this Claimyr thing actually work? I've literally never been able to get through to the IRS no matter when I call. Always get the "due to high call volume" message and then disconnected.
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StormChaser
Come on, there's no way this actually works. The IRS phone system is deliberately designed to be impossible to navigate. And even if you do get through, the agents often give contradictory advice depending on who you talk to. I've wasted entire days trying to get help.
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Dmitry Petrov
It uses some kind of call technology that waits on hold for you and only calls you back once an actual human at the IRS picks up. You don't have to stay on the line waiting - they just call you when someone answers. It's not a scam or anything sketchy - they don't ask for any personal tax info. Regarding inconsistent advice - that can definitely happen, but I've found that if you have a very specific question like "what code to use on form 8949 for this exact situation," they usually give consistent answers. It's more the complex interpretations where you might get differing opinions depending on who you talk to.
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StormChaser
I'm actually shocked. I tried Claimyr after posting my skeptical comment above. I was absolutely certain it was going to be a waste of time, but I got through to an IRS representative in about 20 minutes. The agent confirmed that I should use code B for transactions where basis wasn't reported to the IRS (like the first commenter said), but also helped me figure out how to handle some weird foreign stock situations I had that needed code F. I've been trying to call the IRS for THREE WEEKS on my own without success. Consider me impressed and my skepticism completely gone.
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Miguel Castro
Jumping in a bit late, but wanted to add something that might help with Form 8949. Remember that if you have LOTS of transactions (like more than 10-15), you can actually summarize them rather than listing each one individually. You can attach a statement showing all the details and just put the totals on the form itself. The instructions say you can write "See attached statement" in column (a) and then show the totals in columns (d), (e), (f), and (g). This saved me hours last year when I had over 100 trades to report.
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Giovanni Rossi
AuthorThanks for this tip! I actually have about 20 transactions, so this could definitely save me some time. Do I still need to include the appropriate codes when I summarize the transactions? And do I need to separate transactions with different codes into different summary lines?
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Miguel Castro
You'll need to group transactions with the same code together on your attached statement, and then create separate summary lines on Form 8949 for each code type. So if you have transactions with code B and some with code W (wash sales), you'd have two summary lines with the appropriate code on each. Make sure your attached statement includes all the same information that would be on Form 8949 - including the codes for each transaction. The IRS still needs all the details, you're just moving them to an attachment instead of cramming them all onto the form itself.
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Zainab Ibrahim
Im super confused, on my 1099-B it says basis reported to IRS but still says to use Box B?? shouldnt i be using Box A if the basis was reported? the instructions make no sense
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Fatima Al-Mansour
That does sound confusing! Box A is for transactions where basis WAS reported to the IRS. Box B is for when basis was NOT reported. If your 1099-B specifically says the basis was reported to the IRS, then you should use Box A, regardless of what else it might say about Box B. Double check the wording on your form - sometimes the language can be a bit unclear.
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Diego Rojas
Based on what you've described, it sounds like you should definitely be using Code "B" in column (f) for each transaction line. The other commenters are right - when your 1099-B shows that cost basis information is NOT being reported to the IRS, Code "B" is exactly what you need. Just to clarify the process: You select Box B at the top of Form 8949 (which you've already done correctly), and then you put Code "B" in column (f) for each individual transaction where the basis wasn't reported to the IRS. Make sure you're entering the cost basis information in column (e) since you mentioned you have all the purchase and sale price details. The IRS needs this information even though your broker didn't report it to them directly. One thing to double-check: look at your 1099-B form in Box 12 - it should be blank or show a code that indicates basis wasn't reported. If it shows "B" or is blank, then you're on the right track with using Code "B" on Form 8949.
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