Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

Indie Software Developers - How do I handle taxes?
The "hire a pro" is quite correct, if you are truly making this kind of money. That said, I believe in a certain amount of self-education so you don't follow a pro's advice blindly. First, I wrote an article that discussed Marginal Tax Rates, and it's worth understanding. It simply means that as your income rises past certain thresholds, the tax rate also will change a bit. You are on track to be in the top rate, 33%.  Next, Solo 401(k). You didn't ask about retirement accounts, but the combined situations of making this sum of money and just setting it aside, leads me to suggest this. Since you are both employer and employee, the Solo 401(k) limit is a combined $66,500. Seems like a lot, but if you are really on track to make $500K this year, that's just over 10% saved.   Then, whatever the pro recommends for your status, you'll still have some kind of Social Security obligation, as both employer and employee, so that's another 15% or so for the first $110K.  Last, some of the answers seemed to imply that you'll settle in April. Not quite. You are required to pay your tax through the year and if you wait until April to pay the tax along with your return, you will have a very unpleasant tax bill. (I mean it will have penalties for underpayment through the year.) This is to be avoided.  I offer this because often a pro will have a specialty and not go outside that focus. It's possible to find the guy that knows everything about setting you up as an LLC or Sole Proprietorship, yet doesn't have the 401(k) conversation.  Good luck, please let us know here how the Pro discussion goes for you.