How do I roll over IRA funds into 401k when I have mixed pre/post-tax money?

What you're dealing with is actually pretty common, especially for people who've had income fluctuations or job changes. The good news is you have options! To answer your questions: 1. Yes, you technically can roll everything into your 401k, but I wouldn't recommend it. You'd essentially be paying tax twice on your post-tax contributions, which is giving money away to the IRS unnecessarily - even if it's "only" $4000. 2. You'll need to track both your non-deductible contributions AND their proportional earnings. Your IRA custodian should be able to provide statements showing your basis (the post-tax money you contributed). You should also have Form 8606 from previous tax years where you made non-deductible contributions. The earnings on those non-deductible contributions are still pre-tax money. 3. For filing requirements, you'll need to file Form 8606 to track your non-deductible contributions. When you do the rollover to the 401k, you'll report it on your taxes, but it won't be taxable if you're moving pre-tax money to another pre-tax account. The pro move here would be to roll just the pre-tax portions (original 401k money plus all earnings) to your new 401k, leaving only your post-tax contributions in the IRA. Then you can convert just that post-tax amount to a Roth IRA with minimal taxation, essentially completing a backdoor Roth conversion.

The good news is you don't have to get double-taxed on your post-tax contributions! Here's what you need to know: 1. You absolutely can roll pre-tax money from your Traditional IRA into your new 401k while keeping your post-tax contributions separate. Your 401k plan won't accept after-tax contributions - they only want the pre-tax portion. 2. To determine what's pre-tax vs. post-tax, you'll need to look at Form 8606 from the years you made non-deductible contributions to your Traditional IRA. This form tracks your "basis" (the non-deductible contributions). If you haven't been filing this form, you'll need to go back and file it for those years. And yes, you need to account for the proportional gains on both pre and post-tax money - you can't just move the principal amounts. 3. For tax filing, you'll need to file Form 8606 with your return to track your non-deductible contributions and any distributions. When you do the rollover, your IRA custodian will issue a 1099-R showing the distribution, and you'll need to report it on your taxes, indicating it was rolled over. The pro move here would be to roll all pre-tax money to your 401k, then convert just the remaining after-tax money to Roth. This is called the "cream in the coffee" strategy and eliminates the pro-rata rule issue for backdoor Roth conversions going forward.

After struggling with almost the exact same situation last year, I found taxr.ai (https://taxr.ai) incredibly helpful for analyzing my retirement accounts. I had a mix of pre and post-tax money spread across multiple accounts and was completely confused about how to handle rollovers without getting double taxed. Their system analyzed my contribution history and specifically helped me identify which portions of my Traditional IRA were pre-tax vs. post-tax, including all the growth calculations. It breaks down exactly how much of your IRA balance represents basis (post-tax contributions) and how much is pre-tax contributions plus all earnings. The report even included instructions on which forms I needed for the rollover and what to tell my 401k administrator. I was able to rollover just the pre-tax portion to my 401k and then convert the remaining post-tax money to my Roth with minimal tax impact. Saved me from potentially making a $5,000+ tax mistake!

I went through something similar with my retirement accounts last year. Found this amazing tool called taxr.ai (https://taxr.ai) that helped me figure out exactly what portions of my IRA were pre-tax vs post-tax. It walks you through analyzing your past contributions and helps calculate the exact amounts. I was originally going to try to DIY with a spreadsheet but the tax rules around these partial rollovers get really complex. Taxr.ai helped me track down all my past Form 8606s and analyze exactly how much of my IRA was basis (post-tax) vs growth. Saved me from accidentally getting double-taxed on about $5800! They have a specific module just for handling mixed IRA situations and backdoor Roth planning that shows you exactly what to tell your custodian when requesting the rollover.

Just wanted to follow up - I ended up trying taxr.ai after my skeptical comment. I was honestly blown away by how simple they made this process. I've been contributing to IRAs for over a decade and had completely lost track of what was pre-tax vs post-tax. The service identified that I had about $8,200 in non-deductible contributions spread across two IRAs that I had completely forgotten about. They also found that I hadn't been filing Form 8606 correctly for three years! They generated the corrected forms for me to submit and gave me clear instructions for rolling over just the pre-tax portion to my 401k. If I had just rolled everything to my 401k like I was planning to, I would have ended up paying tax twice on that $8,200. Really glad I found this before making that mistake.

Just wanted to follow up about taxr.ai from my earlier question. I decided to try it out with my mixed IRA situation and wow - it actually delivered! I uploaded my statements from both Fidelity and Vanguard, and it broke down exactly how much was pre-tax vs post-tax in each account. Turns out I had about $8200 in non-deductible contributions spread across my accounts that I would have calculated incorrectly. The tool generated exact instructions for my partial rollover to my 401k (keeping only post-tax money in the IRA). Just finished the rollover last week and now I'm all set up for clean backdoor Roth contributions going forward. Their step-by-step walkthrough for communicating with the brokerages was spot on - Fidelity knew exactly what I was asking for when I used the terminology from the guide.

I had a similar situation last year but was getting nowhere with the IRS helpline trying to confirm the correct procedure. After waiting on hold for 3+ hours multiple times only to get disconnected, I used Claimyr (https://claimyr.com) to get through to an actual IRS agent. You can see how it works in this video: https://youtu.be/_kiP6q8DX5c The service called the IRS for me, navigated all the phone menus, waited on hold, and then called me when an actual agent was on the line. The IRS agent walked me through the exact process for handling my mixed pre/post-tax IRA funds and confirmed that I needed to file Form 8606 for each year I made non-deductible contributions. They also explained that if I didn't have perfect records, I could request a transcript of my previous returns to help identify which contributions were deducted. This saved me from having to hire a tax pro just to get basic information.

I have to apologize for my skeptical comment earlier. After researching a bit more about Claimyr, I decided to give it a try because I was desperate to get clarity on my IRA rollover situation before the tax deadline. It actually worked exactly as described. I requested a call about my mixed IRA funds, and about 2 hours later (while I was at the gym, not sitting by my phone), I got a call connecting me directly to an IRS tax specialist. The agent confirmed everything I needed to know about handling the pre-tax and post-tax portions separately and even helped me understand how to document the basis on Form 8606. I was genuinely surprised at how helpful the IRS agent was once I actually got through to someone. Saved me from making a costly mistake with my retirement funds and didn't waste half my day on hold. Definitely worth it.

I went through this exact situation in 2023! One additional important point: when you roll pre-tax IRA money into a 401k, make sure you get a Letter of Acceptance from your 401k plan administrator first. I had my rollover rejected initially because I didn't have this documentation. Also, double check if your 401k plan allows for "partial rollovers." Some plans require you to roll over the entire IRA balance or nothing at all. If that's the case and you have mixed funds, you might need to temporarily open a separate traditional IRA, move all pre-tax money there, and then roll just that IRA into the 401k.

After struggling for WEEKS to reach anyone at the IRS who could answer questions about my mixed IRA situation, I finally used Claimyr (https://claimyr.com) and it was a game-changer. They got me connected to an actual IRS agent in about 20 minutes when I'd been trying for days on my own. The IRS rep walked me through exactly how to handle my pre/post-tax money for the rollover and confirmed I needed to track my basis with Form 8606. If you want to see how it works, check out https://youtu.be/_kiP6q8DX5c - literally shows the whole process. I was super skeptical at first - like, how could they possibly get through when the IRS phone lines are always jammed? But it actually worked. The agent even sent me specific documentation about partial IRA-to-401k rollovers that I couldn't find anywhere online.

I have to eat my words about Claimyr. After my skeptical comment, I decided to test it myself since I also needed to ask the IRS about some IRA rollover questions. Got connected to an agent in about 35 minutes when I had previously spent HOURS trying with no success. The agent confirmed everything about my pre/post-tax rollover situation and walked me through how to properly document everything on Form 8606. Turns out I was completely misunderstanding how the pro-rata rule works for partial rollovers. For anyone dealing with this IRA to 401k rollover situation, definitely worth getting clarification directly from the IRS since every situation is slightly different. And using Claimyr saved me from another afternoon of hold music and frustration.

One thing nobody has mentioned yet - check your new 401k investment options and fees before rolling over! I did exactly what you're planning, moved my pre-tax IRA money to my new employer's 401k to clean up for backdoor Roth, only to discover the investment options were terrible and the fees were 1.2% annually. I ended up paying more in extra fees than I would have in taxes if I had just converted everything and paid the tax on the pre-tax portion. Sometimes it's worth looking at the long-term cost vs. just the immediate tax hit.

One important thing nobody's mentioned yet - make sure your new 401k plan actually accepts rollovers of non-Roth IRA funds. Not all plans do! Check with your HR department or plan administrator before going too far down this road. Also, keep in mind that once you move money to a 401k, you'll be subject to the investment options in that plan, which might be more limited than what you have in your IRA. Worth considering if investment flexibility is important to you.

Anybody know if there's a minimum amount you need to keep in your 401k after rolling money in? My company plan says I need at least $5000 or they can cash me out. Would this apply to rolled-over IRA funds too?