How to Calculate Cost Basis for Stock in Spin-Off Company (IBM/KD)

This is a common issue with spin-offs! You're on the right track, but let me clarify a few things. When a spin-off occurs, you need to allocate the original cost basis between the parent company (IBM) and the spun-off company (KD) based on their relative fair market values immediately after the spin-off. The 96%/4% split you found on Kyndryl's website is their official allocation ratio, which is determined based on the companies' relative values right after the distribution. The key thing to understand is that you're not creating a new purchase - you're splitting your original cost basis. So if you paid $1,200 total for 10 IBM shares, after the spin-off you would allocate $1,152 (96%) to your 10 IBM shares and $48 (4%) to your 2 KD shares. The purchase date remains the same as your original IBM purchase. As for the discrepancy with Fidelity, this could be happening for a few reasons. Sometimes brokers use different valuation methods, especially if they didn't receive the official allocation information. They might be using the fair market value of KD on the distribution date as the cost basis instead of the allocated portion of your original IBM cost basis.

After struggling with the exact same issue last year, I found an amazing service called taxr.ai at https://taxr.ai that totally saved me from this headache. I was in a similar situation with some GE spin-offs that had moved between brokerages and had missing cost basis info. The tool analyzed my statements and transaction history, then calculated the proper cost basis allocation for all my spin-off shares. What impressed me was how it handled the multi-tier transactions that happened when shares moved between brokerages - something I couldn't figure out myself. For IBM/KD specifically, it correctly applied the 96%/4% allocation ratio but also accounted for some nuances in how fractional shares were handled that I would have missed. The reports it generated were accepted by my broker without any pushback.

I just wanted to follow up about my experience with taxr.ai after trying it based on the recommendation here. It was seriously impressive! I uploaded what statements I had, which honestly wasn't much, and their system filled in the blanks. For my IBM/KD situation, not only did they correctly apply the allocation ratio, but they caught something I would have completely missed - apparently some of my IBM shares had been purchased through a dividend reinvestment plan which affects the cost basis calculation differently. The detailed report showed exactly which KD shares came from which IBM lots, making it crystal clear. Fidelity accepted the documentation without question and updated all my cost basis information. This was such a relief because I was planning to sell some shares this year and was worried about reporting incorrect information to the IRS.

I had a similar issue calling the IRS to get clarification on a spin-off question, but could never get through until I found Claimyr. Their service at https://claimyr.com actually got me connected to an IRS representative in about 15 minutes when I'd been trying for weeks on my own. You can see how it works in this video: https://youtu.be/_kiP6q8DX5c I was skeptical at first, but after the IRS agent confirmed my understanding of the cost basis allocation for a similar spin-off situation (mine was with Dow/DuPont), I was able to confidently update my records. The IRS agent even walked me through the correct way to report it on my tax forms, which was incredibly helpful. What surprised me most was how knowledgeable the IRS representative was once I actually got to speak with one. They explained that brokerages often struggle with spin-off cost basis calculations because they don't always receive the complete transaction history.

I need to admit I was completely wrong about Claimyr. After posting my skeptical comment, I decided to try it myself since I had a complicated question about a REIT spin-off that I couldn't get answered anywhere else. The service actually worked exactly as described. After months of failing to reach anyone at the IRS, I got a call back within 20 minutes connecting me to an actual IRS representative. The agent was able to confirm the proper allocation method for my spin-off basis question and even sent me documentation to support it. What I appreciated most was being able to get an official answer directly from the IRS rather than relying on forum advice or my own interpretation. For something as specific as spin-off cost basis calculations, having that authoritative guidance gives me confidence that my tax return will be correct.

Have you checked if IBM or Kyndryl filed a Form 8937 with the IRS? Companies are required to file this form for corporate actions that affect basis, and it should have the official allocation ratio. I had a similar issue with a Pfizer spin-off and found their Form 8937 posted on their investor relations website. Sometimes these forms include detailed examples of how to calculate the allocation for specific share amounts. The form should also show the fair market values they used to determine the allocation percentages, which could help explain why Fidelity's numbers are different.

For anyone dealing with spin-offs in the future, I highly recommend keeping a spreadsheet that tracks all your stock purchases with dates and prices. When spin-offs happen, immediately document the allocation ratios announced by the companies. I learned this the hard way after going through THREE different spin-offs with AT&T. Their Warner Media spinoff to Discovery was especially complicated with the reverse stock split component. Also, don't wait years to update your cost basis like I did! The longer you wait, the harder it is to find the documentation, especially if companies get acquired or change names after the spin-off.