EIN
What is an EIN?
A nine-digit number the IRS gives your company — an ID number for the business. You need one to open a US bank account, use Stripe or PayPal, sell on Amazon, or file anything with the IRS. The number itself is free from the IRS.
EIN stands for Employer Identification Number. Despite the name you do not need employees to have one, and most companies that hold an EIN never hire anybody. It is simply how the IRS tells one business from another, in the same way a Social Security Number identifies a person.
A US company is close to unusable without one. Banks ask for it before opening an account. Stripe, PayPal and Amazon ask for it during onboarding. Every filing your company makes to the IRS carries it. If you have registered a US LLC and stopped there, the EIN is the next thing standing between you and a working company.
Applying is free. If you hold a US Social Security Number you can get one on the IRS website in minutes, and you should — paying anybody for that is paying for nothing. Without an SSN the online route is closed to you, and the application has to go to the IRS on paper, by fax or post.