Important point that nobody has mentioned yet - if you're regularly dealing with large cash transactions like this, you should consider setting up a more formal business structure and possibly getting a tax professional. Form 8300 requirements are just one aspect of cash business compliance - there are also state reporting requirements in some locations that kick in at different thresholds.

One thing I haven't seen mentioned yet is that you should also be aware of the timing requirements for Form 8300. You have to file it within 15 days of receiving the cash payment (or the final payment if it's a series of related transactions). This is crucial because there are penalties for late filing, even if it's just a few days late. Also, don't forget that you're required to provide a written statement to the customer by January 31st of the year following the year you filed the form. Many small business owners miss this requirement, but it's just as important as filing the form itself. For your phone flipping business, I'd recommend setting up calendar reminders for both the 15-day filing deadline and the January 31st customer notification deadline. Missing these deadlines can result in penalties that really add up, especially if you're filing multiple forms throughout the year.

Dont forget to check if your state has different capital gains rates than federal! I got burned on this last year - my state treats all capital gains as ordinary income so I ended up paying a higher rate than I expected.

Great thread with lots of helpful info! Just wanted to add one more consideration that saved me some money when I sold land last year - don't forget about selling expenses when calculating your basis. You can add legitimate selling costs like real estate agent commissions, attorney fees, title insurance, transfer taxes, and even advertising costs to your basis. This reduces your taxable gain dollar-for-dollar. In my case, I had about $3,500 in selling expenses that I almost forgot to include. That reduced my capital gain by $3,500, saving me around $525 in taxes (15% federal rate). Make sure you keep all receipts related to the sale - they're deductible against your gain!

Doesnt the 100% safe harbor only work if ur current year income is under 150k? If ur making big capital gains and going over 150k total, dont u need to pay 110% of last years taxes to meet safe harbor??

I went through this exact same situation last year after selling some stocks that had appreciated significantly. The key thing that helped me was understanding that the safe harbor rule is designed to protect you from penalties, not necessarily minimize your total tax bill. In your example, if you paid $32k last year and have $13k withheld this year, making $19k in estimated payments would indeed meet the 100% safe harbor requirement and protect you from underpayment penalties. You'd still owe the remaining ~$33k when you file, but without the penalty. One practical tip: I found it helpful to make the estimated payment as soon as possible after realizing the gains rather than waiting until the quarterly due date. This shows good faith effort to the IRS and gives you more time to adjust if you realize you've miscalculated something. Also, don't forget that if you have any other withholding sources (like a spouse's job or 1099 work), those count toward your safe harbor amount too. The IRS really does treat all payments equally - withholding, estimated payments, and even overpayments from prior years all count.

I'm dealing with this exact same situation right now as a new S-Corp owner! Reading through all these responses has been super helpful, especially the real audit experience from Daniel. It sounds like the consensus is pretty clear - if you're actively working in the business, you need to pay yourself a reasonable salary regardless of distributions. What I'm taking away is that I need to start documenting everything now: my hours worked, what comparable positions pay in my industry/area, and my business financial situation. Even if I can't afford a full market-rate salary right now during my growth phase, having that documentation seems crucial for justifying whatever salary I do set. Has anyone found good resources for researching what "reasonable compensation" actually means for their specific role and industry? I'm trying to figure out if there are standard databases or surveys that the IRS typically references during audits.

As a tax professional who deals with S-Corp audits regularly, I want to emphasize something that hasn't been fully addressed here - the IRS has gotten much more aggressive about this issue in recent years. They've actually developed algorithms to flag S-Corps with active owners who report zero or unusually low W-2 wages compared to their business income. The "reasonable compensation" requirement exists because S-Corp distributions aren't subject to self-employment tax (Social Security/Medicare), while salaries are. If you're working in the business but taking no salary, the IRS sees this as tax avoidance, pure and simple. Here's what I tell my S-Corp clients: even if your business is in a growth phase and cash is tight, you need SOME salary if you're actively working. The IRS would rather see you document a reduced but defensible salary (maybe 60-70% of market rate) with clear business justification, rather than zero salary with the excuse that you're reinvesting everything. Start paying yourself something now, even if it's conservative. Document your reasoning, keep records of comparable positions, and track your hours. This proactive approach will save you significant headaches and penalties down the road.

One thing nobody's mentioned - distributions aren't subject to payroll taxes, but they ARE subject to income tax. The tax advantage of an S-corp comes from paying reasonable salary (subject to both income + payroll tax) and taking remaining profits as distributions (subject to only income tax). But you still need to pay yourself something as W-2 wages.

I've been running an S-corp for 5 years and went through this exact confusion early on. The bottom line is you absolutely cannot just pay the tax obligations without actually distributing salary to yourself - that's considered tax evasion by the IRS. Here's what I learned the hard way: "reasonable compensation" means you must receive actual W-2 wages for services performed, run through normal payroll with proper withholdings. The IRS specifically looks for S-corp owners trying to avoid payroll taxes by skipping salary altogether. My recommendation: determine a reasonable salary based on what you'd pay someone else to do your job, then take that as actual payroll. Everything above that reasonable amount can stay in the business as retained earnings or be distributed later. Don't try to game the system - the audit risk isn't worth it, and the penalties can be severe if they reclassify your distributions as wages subject to back payroll taxes plus interest.