EIN
The business's federal tax ID: nine digits, free from the IRS. You need it for payroll, a bank account and most business returns.
An employer identification number, or EIN, is a business's federal tax ID. The IRS uses it to track business returns, payroll deposits and information returns.
The IRS EIN page says "You never have to pay a fee for an EIN." You apply online at IRS.gov. The application asks for the responsible party's Social Security number or ITIN, and the IRS issues only one EIN per responsible party per day. The online service has set hours rather than running around the clock.
You need one to run payroll, to file as a corporation or partnership, and to elect S corp status. Banks also ask for one to open a business account. A single-member LLC that has employees needs its own EIN for payroll even though it is disregarded for income tax, per the IRS LLC page.
Get the EIN after the state approves your LLC or corporation, so the legal name matches. Websites that charge for an EIN are charging you to fill in a free IRS form.