Make money first :
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If you choose to file yourself, you can fill out a form and send in the application to the PA State Department (https://www.dos.pa.gov/BusinessCharities/Business/Resources/Pages/Pennsylvania-Limited-Liability-Company.aspx)
If you want to rely on a 3rd party, LegalZoom will work (https://www.legalzoom.com/business/business-formation/llc-overview.html)
If you choose to do it yourself, keep in mind you will have to manage your taxes and annual reporting to the State Gov't. It is not complicated but requires ownership responsibility.
**I'd suggest searching on Google "quickest way to form LLC reddit" to gain additional information about forming an LLC. Additional reading should also consider writing a business plan to validate your business idea before starting an LLC. It could be unnecessary to form an LLC until you generate revenue or have a fundamental business plan in place that shows a clear go-to-market strategy and viable business model. And this process takes even more time, strategy to get right.
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This comes up every single day in this sub and r/Entrepreneur and everyone gives helpful links to where you can file for incorporation online, etc.
But the big question is, WHY? Why are you forming an LLC? If the reason is because you think that it's required for you to start a business, it's not - you can operate a business (called a "sole proprietorship") right now without any government involvement, forms, or anything else.
Just start your business - right now, today - by going and getting clients and getting to work. You do NOT need an LLC, you do NOT need a business bank account, and you do NOT need an EIN. All of those things are helpful (and become necessary as you grow), but you can start a business without filing or doing anything.
All you need to do is keep accurate, detailed records of any money you spend on business-related expenses, as well as records of all revenue that you generate (money you get from your customers). With those records, you could go on to get an accountant or set up QuickBooks or whatever, or you could just do your own taxes with TurboTax or similar and just fill out Schedule C on your 1040 (where you list your total expenses, total revenue, and pay taxes on the difference (your income, aka profit for this simple example)).
Go - start now, get your first customer, get them to write you a check or give you cash, or set up one of the myriad of free "process credit cards with your phone" apps. Have them write the check to your personal name, and just document the amount and the reason, and you'll be good.
Worry about the LLC and all of the other stuff later, once your business is taking off - for now, don't let paperwork get in the way of getting started.
Note that this advice doesn't apply if you're in a business that might need a license of some sort - food truck, vendor, selling products in person from a storefront (especially food), etc. For web design, you're just fine with no paperwork at all
Edit: I made this post many years ago; if you are reading it, please don't message me for advice. I get so many messages and I just can't help everyone; there are plenty of other resources out there but my best advice for you is just START NOW doing your business idea, don't worry about incorporation and all that stuff; you can deal with that once you have made a few dollars from the business. Good luck with your business
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