Do I need an EIN, and how do I get one?

An EIN (Employer Identification Number) is a federal tax ID for your business, like a Social Security number for the entity. You need one if you have employees, run an S-corp or partnership, or want to open a business bank account; even a solo sole proprietor often gets one to avoid putting their SSN on W-9s sent to clients. Getting it is free and fast: apply directly on the IRS website and you'll receive the number immediately — never pay a third-party site that charges for this. Avoid services that mark up the free EIN application. Once you have it, use it on client paperwork, payroll, and business accounts. Keep the confirmation letter (CP 575) somewhere safe; banks and lenders sometimes ask for it.