Key Takeaways The IRS aggressively pursues worker misclassification cases, reclassifying independent contractors as employees and assessing back employment taxes The common law test and the IRS 20-factor analysis examine behavioral control, financial control, and relationship type to determine worker status Section 530 relief provides a powerful safe harbor defense for businesses with a reasonable basis for independent contractor classification Form SS-8 determinations by the IRS can trigger full employment tax audits Reclassification consequences include back FICA taxes, income tax withholding, penalties, and interest — potentially reaching back three or more years Understanding Worker Classification Disputes Worker classification — whether a worker is an employee (W-2) or an independent contractor (1099) — is one of the most consequential and frequently resolved issues in business tax law. The distinction affects employment tax obligations, income tax withholding, benefit eligibility, labor law protections, and a host of other legal and financial considerations. The IRS has identified worker misclassification as a major source of the "tax gap" and has dedicated significant resources to enforcement. When the IRS determines that a business has misclassified employees as independent contractors, the consequences are severe. The business becomes liable for the employer's share of FICA taxes (Social Security and Medicare) that should have been withheld, the employee's share of FICA taxes, federal income tax withholding (or a percentage thereof), and substantial penalties and interest on all of these amounts. For businesses with many misclassified workers over multiple years, the total assessment can be catastrophic. At Neil Jesani Tax Resolution , we have extensive experience defending businesses against IRS worker classification challenges. Understanding the legal tests, available defenses, and strategic options is essential for any business that relies on independent contractors. The Common Law Test The IRS and courts use the common law test to determine whether a worker is...