The IRS issues EIN to identify your business while ITIN is used to identify you as a tax-liable person in the US. If you are a sole proprietor or an owner of a single-member LLC, you can use your ITIN in IRS forms for your business. In other cases, you must get an EIN to file your taxes. We advise you to get an EIN even though you do not have to get one to separate your personal and business tax dealings.