For a freelancer, consultant or agency abroad, the point of a US company is that a US client's finance team can pay it like any other supplier: a vendor record, an invoice, a tax form on file, and an ACH transfer that lands a day or two later. Here's that process from the client's side, so you can hand over what they need before they ask.
The vendor record
The client's system wants the company's legal name, address, EIN, bank details and a tax form. The name and EIN come from the IRS letter. The address is the company's own, or a mailing address if you have one. The bank details are the US account and routing numbers from Mercury, Wise Business or similar. Send everything in one message, in the format the client's template asks for, and the record is usually set up within a day or two.
The tax form
A client paying a US company asks for a W-9. A multi-member LLC or a corporation gives one, with its EIN. A single-member LLC with a foreign owner gives a W-8BEN in the owner's name instead, because the IRS looks through the LLC to you, and the IRS's instructions say so. Some accounts teams haven't seen this before, so point them to the instructions and give them the W-8BEN. Either way, nothing is withheld on payments for services performed outside the US. The W-8BEN guide walks through the form.
The invoice
Invoice from the company, not from you: its name and address, its EIN if the client wants it shown, an invoice number, the date, the service, the amount in dollars, the payment terms and the bank details. Net 30 is standard in the US and net 15 is common for small suppliers, so say which on the invoice. Every plan includes invoicing, and its invoices carry the details a US client expects.
How the money moves
Bringing it home
Get paid in dollars, pay the company's costs in dollars, and move what you take out through Wise or a similar service at close to the mid-market rate. Record each transfer to yourself as a distribution, because that's what Form 5472 reports. Your own country's rules on receiving foreign currency still apply, and the country pages note where they matter.
When a client won't pay a foreign-owned company
Occasionally a client's policy excludes suppliers with foreign owners, usually for government contracts or regulated industries. No form changes that, so ask early. If that's their policy, a US LLC won't get you the contract.