What code should I put on form 8949 for unreported cost basis?

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.

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.

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.

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.

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.

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.

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

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.

Just wanted to share my experience since I was in almost exactly the same situation last year. I had multiple 1099-B forms showing short-term transactions where the cost basis wasn't reported to the IRS, and I was totally lost on the codes. After reading through all the responses here, I can confirm that Code "B" is definitely the right choice for your situation. I used it for all my transactions where basis wasn't reported, and my return was accepted without any issues. One tip that saved me time: if you're using tax software like TurboTax or FreeTaxUSA, they usually walk you through this automatically when you import your 1099-B. The software will ask you questions about whether the basis was reported and then assign the correct codes for you. But if you're doing it by hand, Code "B" is what you need. Also, don't overthink the instructions - they can be really confusing, but your situation is actually pretty straightforward. You have the cost basis info, your broker just didn't report it to the IRS, so you report it yourself with Code "B". That's it!

I just wanted to add one more thing that might help - when you're filling out Form 8949, make sure you're consistent with how you report the dates. I made the mistake last year of using different date formats (some MM/DD/YYYY, some MM/DD/YY) and it caused some confusion when I was double-checking my work. Also, if you have a lot of transactions from the same broker, they should all follow the same pattern regarding whether basis was reported or not. So once you confirm that Code "B" is right for one transaction from that broker, it should apply to all the others from the same source. The good news is that this is actually one of the more straightforward situations with Form 8949 - you're not dealing with wash sales, foreign transactions, or other complex scenarios. Just Code "B" for unreported basis, and you should be all set. Good luck with finishing your taxes!

I went through this exact same situation last year and can confirm that everyone's advice about using Code "B" is spot on. What really helped me was creating a simple spreadsheet to track all my transactions before transferring them to Form 8949 - it made the whole process much less overwhelming. One thing I'd add is to keep copies of all your brokerage statements and trade confirmations, even after you file. The IRS occasionally asks for documentation to support the cost basis information you're reporting, especially when it wasn't reported by your broker. Having everything organized made it easy when I got a letter asking for clarification on a few transactions. Also, if you're doing multiple forms (like if you have both short-term and long-term transactions), make sure you're using the right boxes at the top. It sounds like you've got this figured out with Box B for short-term unreported basis, but it's easy to mix them up when you're dealing with multiple forms. The whole process gets much easier once you do it the first time - I was stressed about it last year but this year it took me maybe 30 minutes to complete all my 8949 forms. You've got this!

I just wanted to chime in as someone who's been through this exact scenario multiple times. Code "B" is absolutely the right choice for your situation - when your 1099-B shows that cost basis wasn't reported to the IRS, that's exactly what Code "B" is designed for. One thing that might help ease your mind: this is actually a very common situation, especially with certain brokers who don't report cost basis for all types of transactions. The IRS is completely used to seeing Code "B" on Form 8949, and as long as you have your purchase records to support the cost basis you're reporting, you're in good shape. I'd also recommend double-checking your math before submitting - make sure the gain/loss you calculate by subtracting your cost basis (column e) from the proceeds (column d) makes sense based on what you remember about those trades. It's an easy way to catch any data entry errors before filing. You're doing everything correctly by selecting Box B at the top and using Code "B" for each transaction. Don't let the complexity of the instructions psych you out - your situation is straightforward and you've got all the information you need to file accurately.