A Tax ID, or Tax Identification Number, is a unique identifier assigned to individuals and businesses for tax purposes. It helps the Internal Revenue Service (IRS) and other tax authorities track income, tax obligations, and ensure compliance with tax laws. Individuals may have a Social Security Number (SSN) as their Tax ID, while businesses typically use an Employer Identification Number (EIN). Tax IDs are essential for filing tax returns, opening bank accounts, and applying for loans. They help prevent identity theft and ensure that taxpayers are accurately identified in the tax system. Keeping your Tax ID secure is important to protect against fraud.