Authors who self-publish generally don’t need an Employer Identification Number (EIN).
Should you ghostwrite books or freelance, however, you probably will need one. That’s because anyone who pays you more than $600 annually to a client needs to file a 1099 form with the Internal Revenue Service. As part of that form, the client will need to know your EIN.
Another instance where you may need one is if opening up a special bank account for yourself as a sole proprietor to keep your author earnings and spending separate from your personal bank account. Most banks will require that you have an EIN to open such an account.
For the person who hired you, giving them your social security number rather than an EIN is perfectly fine. An EIN, however, probably gives you more protection against identity theft.
An EIN is obtained solely from the IRS. It is free and can be applied for online. There’s never a need to pay a service for obtaining an EIN for you.
Self-published authors usually don’t need EIN
