I went through something very similar when I returned from working in Canada for 4 years. The key thing to understand is that the FINCEN 105 is purely a customs/border security requirement - it has nothing to do with your taxes directly. Since you've been filing US tax returns all along while abroad, you've likely already reported the income that became these savings in previous years (either as foreign earned income or after applying foreign tax credits). The physical act of bringing the money into the US doesn't create a new taxable event. However, don't forget about the ongoing FBAR requirement if you still have foreign accounts. Even after moving back, if you had signature authority over foreign accounts totaling $10,000+ at any point during the tax year, you still need to file the FBAR by April 15th (with automatic extension to October 15th). One practical tip: when you deposit that $16K into your US bank account, consider doing it in smaller amounts over a few weeks rather than all at once. While there's nothing illegal about depositing the full amount, banks are required to report cash deposits over $10K, and spreading it out can avoid unnecessary paperwork and potential delays in accessing your funds.

As someone who works in international tax compliance, I want to emphasize that you've already handled the most important step correctly by filing the FINCEN 105 at entry. This is exactly what you're supposed to do when bringing $10K+ in cash across the border. Since these are personal savings from income you've already reported on previous tax returns while abroad, you're right that this isn't "new income" to report. The key things to remember going forward: 1. Keep records of your FINCEN 105 filing (date, port of entry, amount declared) with your tax documents 2. Continue filing FBAR if you still have foreign accounts totaling $10K+ at any point during the year 3. Don't forget about Form 8938 if your foreign assets exceed the reporting thresholds 4. Make sure you're claiming all eligible foreign tax credits from taxes paid abroad The complexity you're dealing with is very common for returning expats. The IRS actually has Publication 54 (Tax Guide for U.S. Citizens and Resident Aliens Abroad) which covers many of these scenarios. Consider consulting with a tax professional who specializes in international taxation if your situation involves significant amounts or multiple countries - the rules can be intricate and the penalties for mistakes can be substantial.

Is there any way to find out if your employer's 401k plan supports the mega-backdoor option without having to call them? Mine has a website but its terribly designed and the FAQs don't mention anything about after-tax contributions or in-plan conversions.

Great question about the mega-backdoor Roth! To address your specific situation - since your employer contributions are already bringing you close to the $69k limit, you likely don't have much room for the after-tax contributions that make the mega-backdoor strategy possible. Regarding your $22.5k traditional 401k contributions, you generally can't go back and convert those to Roth within the 401k after they've already been made. However, you might be able to roll them to a traditional IRA and then do a Roth conversion (though this would trigger taxes on the converted amount). For previous years, unfortunately you can't retroactively make mega-backdoor Roth conversions. The contribution limits and tax years are fixed once they've passed. But going forward, if you have any room between your total contributions and the annual limit, you could potentially start using the strategy. I'd recommend checking with your plan administrator to see exactly how much contribution space you have after employer matching, and whether your plan allows after-tax contributions and in-plan Roth conversions. Even a small amount of extra Roth space could be beneficial over time.

This thread has been incredibly helpful! I was in almost the exact same situation as the original poster - making around $30k and maxing out my 401k, then getting confused about IRA limits. What really clicked for me reading through these responses is the distinction between "earned income" (which includes your 401k contributions) and "taxable wages" (Box 1 on your W-2, which doesn't). I had been looking at Box 1 and thinking that was my limit for IRA contributions. It's also reassuring to see multiple people confirm this with actual experience and even official IRS confirmation. The tax code can be so confusing, especially when you're trying to optimize multiple retirement accounts at once. Thanks to everyone who shared their knowledge and resources - this community is awesome for getting reliable tax advice!

This is exactly the kind of question that shows how unnecessarily complex the tax code can be! I went through this same confusion when I started maximizing both my 401k and IRA contributions. To add to all the great explanations here: think of it this way - your employer reports your full gross wages to the Social Security Administration and for Medicare purposes regardless of your 401k contributions. That's the same income base the IRS uses for determining IRA contribution eligibility. One thing I didn't see mentioned is that this rule also applies to other pre-tax deductions like health insurance premiums, HSA contributions, and flexible spending accounts. None of these reduce your "earned income" for IRA purposes, even though they all reduce your taxable wages in Box 1 of your W-2. The IRS basically wants to make sure you can't game the system by loading up on pre-tax deductions to artificially lower your earned income and then claim you can't contribute to retirement accounts. It's actually designed to help savers, not hurt them!

Just a heads up - while this strategy works, remember that if your state refund gets delayed for any reason (audits, verification, etc.), you'll still be on the hook for paying federal taxes by the deadline. Might be good to have a backup plan just in case. And definitely e-file both returns for fastest processing!

Great advice from everyone here! Just wanted to add that you should also check if your state has any specific timing for refund processing. Some states are faster than others - for example, California typically processes e-filed returns with direct deposit in 7-10 days, while other states might take 2-3 weeks. You can usually find current processing times on your state's tax department website. This will help you plan better for timing your federal payment. Also, if you're really cutting it close to the April 15th deadline and your state refund hasn't arrived yet, remember you can always pay the minimum amount to avoid penalties and then pay the rest when your refund comes in.

But wait - doesn't the FAA require flight logs anyway? Couldn't you just use those same logs to mark which flights were business vs personal? Seems like aircraft would actually be easier to track than cars since there's already mandatory record keeping.

Your friend is definitely confused about the GSA vs IRS distinction. As a tax professional, I see this mistake frequently with pilots and boat owners who think there are standard mileage rates for all vehicles. The $1.74/mile GSA rate is specifically for federal employees using personal aircraft on official government business - it's a reimbursement rate, not a tax deduction. The IRS Publication 463 is crystal clear that standard mileage rates only apply to "automobiles, vans, pickups, and panel trucks." For his Cessna, he needs to track actual expenses (fuel, oil, annual inspections, insurance, hangar rent, depreciation) and multiply by his business use percentage. The good news is this often results in larger deductions than any hypothetical standard rate would provide, especially when you factor in depreciation on the aircraft value. Tell your friend to keep detailed logs of business flights with dates, destinations, business purpose, and passengers. The IRS loves documentation when it comes to aircraft deductions since they're frequently audited.