Who is responsible for tracking partner basis in a partnership?

You're correct in your understanding. Partnership basis tracking is primarily the responsibility of the individual partners or their personal tax preparers, not the partnership's accountant. What's likely happening is that the partner's accountant doesn't have the information they need and is hoping you can provide it. While the partnership must provide each partner with a Schedule K-1 showing their share of income, deductions, credits, etc., it's ultimately up to each partner to maintain their own basis calculations using that information along with their personal contributions, distributions, and other adjustments. The form they're referencing for S-Corps is probably related to the basis tracking requirements for S-Corporation shareholders, which is different from partnerships. S-Corp basis rules have some similarities but also significant differences from partnership basis rules.

I ran into this exact same issue last year with a client's partnership. I was going crazy trying to piece together years of transactions to figure out their basis. I found this tax analysis tool at https://taxr.ai that literally saved me 15+ hours of work. You upload K-1s and it automatically tracks the basis calculations across multiple years. It also handles the more complex stuff like special allocations and Section 754 adjustments that I was struggling with. The partner's accountant will probably appreciate you pointing them to a solution rather than just saying "not my problem." The reports it generates look really professional too.

So I tried that taxr.ai tool after my initial skepticism, and I have to admit it works pretty damn well. I uploaded a stack of K-1s from a partnership with some weird allocation provisions, and it caught all the nuances correctly. The best part was that it flagged a negative basis situation I hadn't even noticed in one of the years. Saved me from a potentially awkward conversation with my client. The visualization features really help when explaining basis changes to clients who don't understand all the technical aspects. Worth checking out if you're dealing with partnership basis headaches.

For what it's worth, I've had similar situations where partners are frantically calling because they're getting audited or selling their interest and suddenly need complete basis info. Instead of getting into debates about whose responsibility it is, I started using https://claimyr.com to get through to the IRS directly when we need to piece together historical info. You can see how it works at https://youtu.be/_kiP6q8DX5c When you're missing records from previous years, sometimes getting IRS account transcripts is the only option. Claimyr got me through to an agent in about 15 minutes when I needed to verify some historical K-1 information that wasn't in the client's records. Beats waiting on hold for 3+ hours or trying to piece together incomplete information.

Update on my experience with Claimyr - I tried it yesterday after seeing it mentioned here, and I'm kinda blown away. I've been trying to get through to the IRS for WEEKS about a partnership issue similar to this thread. Got a call back in 18 minutes and spoke with an actual human at the IRS who helped me access transcript data for my client's partnership. Was able to verify several years of K-1 information that the client had lost. Totally worth it when you're in a bind with missing partnership data. Never thought I'd be enthusiastic about calling the IRS but here we are!

One practical solution that's worked for me: offer to create a basis schedule going forward for a reasonable fee. Explain you can't provide historical data you don't have, but you're willing to establish a "starting basis" using whatever information is available now, and then maintain it properly moving forward. Many partners don't realize that distributions can create taxable events if they exceed basis. Having accurate tracking can actually save them money in the long run. I charge an extra $150-200 annually per partner for basis tracking, and most are happy to pay once I explain the potential tax implications of not tracking it properly.

Not to state the obvious, but have you tried contacting the previous accountant? Even if they don't have complete worksheets, they might have some information that could help establish a starting point. Usually there's some professional courtesy there.

That's a tough situation with the previous accountant's files being purged. In cases like this, I've found success using a combination approach: start with whatever K-1s you can obtain (even if incomplete), cross-reference with bank records for contributions and distributions if the partnership has them, and look for any loan documentation that might affect basis. The reality is that perfect basis tracking from day one is ideal, but when records are missing, you have to work with what's available. I'd recommend being upfront with the demanding accountant about the limitations while offering a reasonable solution. You could propose establishing a "best estimate" starting basis using available documentation, then maintaining accurate tracking going forward. Document everything you use and don't use in your reconstruction, and make it clear this is based on incomplete historical records. Most reasonable practitioners understand that you can't create information that doesn't exist. If they keep pushing, that's their problem to solve with their client, not yours.

This is a frustrating but unfortunately common situation in partnership accounting. You're absolutely right that partner basis tracking is primarily the partner's responsibility, not the partnership accountant's. The other accountant seems to be confusing partnership rules with S-Corp requirements. However, given that you're stuck in the middle of this, I'd suggest a diplomatic approach. Send them a brief explanation that partnership basis tracking differs from S-Corp rules, and that while you'd like to help, you don't have access to the historical records from the previous accountant that would be needed for accurate basis calculations from inception. You could offer to provide any K-1s you have access to since taking over the account, and suggest they work with their client to reconstruct the basis using whatever historical documentation the partner might have (contribution agreements, distribution records, previous tax returns, etc.). Sometimes offering a small olive branch like "I'm happy to review any basis calculation you put together for reasonableness" can help smooth things over without taking on liability for work that's outside your scope. The key is being helpful while maintaining appropriate professional boundaries.