One of the most consequential decisions a growing business makes is how to classify the people who work for it. Treating a worker as an independent contractor when they should be classified as an employee — or vice versa — has real tax consequences, and the IRS takes misclassification seriously.

This article covers how the IRS determines worker classification, what the tax differences are for the business, and what happens when workers are misclassified.

How the IRS Determines Classification

The IRS uses a common law test that examines three categories of factors:

• Behavioral control: Does the business control how the worker does the job — not just the result, but the method? Does the business provide training, set work hours, or dictate where the work is done? Greater control points toward employee status.
• Financial control: Does the worker have a significant investment in their own tools or facilities? Can the worker work for multiple clients? Is the worker paid a flat fee per project or an hourly rate? Independent contractors typically have more financial independence.
• Type of relationship: Is there a written contract? Does the business provide benefits (health insurance, vacation, retirement)? Is the relationship permanent or for a specific project? Permanent, benefit-providing relationships suggest employment.

No single factor is determinative. The IRS looks at the overall picture. A worker can be an independent contractor even if they work primarily for one client — but the more control the business exercises, the more likely the worker is an employee.

Tax Differences: Employee vs. Contractor

The tax treatment differs significantly depending on classification:

• Employees: The business withholds federal income tax, Social Security (6.2%), and Medicare (1.45%) from wages. The business also pays the employer's matching share of Social Security and Medicare, plus FUTA and state unemployment taxes. The business issues a W-2 at year-end.
• Independent contractors: The business pays the full contracted amount with no withholding. The contractor is responsible for their own self-employment taxes (15.3% on net earnings up to the Social Security wage base). The business issues a Form 1099-NEC for payments of $600 or more.

For the business, using independent contractors avoids the employer's share of FICA taxes, unemployment taxes, and the administrative burden of payroll. This is why some businesses are tempted to classify workers as contractors even when the relationship looks more like employment.

New York State Classification Rules

New York State applies its own worker classification rules, which are generally stricter than the federal standard. New York uses an "ABC test" for unemployment insurance purposes: a worker is presumed to be an employee unless the business can demonstrate all three of the following:

• The worker is free from control and direction in performing the work
• The work is performed outside the usual course of the business or outside the business's place of business
• The worker is customarily engaged in an independently established trade, occupation, profession, or business

Failing the ABC test means the worker is treated as an employee for New York unemployment insurance purposes, even if the federal analysis might reach a different conclusion.

Consequences of Misclassification

If the IRS determines that workers were misclassified as independent contractors, the business can be assessed:

• Back payroll taxes (employee and employer shares of FICA)
• Federal and state unemployment taxes
• Failure-to-withhold penalties
• Interest on unpaid taxes
• Potential penalties under Section 3509 (reduced rates if the business had a reasonable basis for the classification)

Section 530 relief may be available if the business had a reasonable basis for treating workers as contractors — such as reliance on a court decision, IRS ruling, or long-standing industry practice. This relief does not apply if the business failed to file required 1099s.

When to Get a Formal Determination

If you are uncertain about how to classify a worker, you can file Form SS-8 with the IRS to request a formal determination. The IRS will review the facts and issue a ruling. This process takes time (often several months), but it provides certainty and protection against future misclassification claims.

For businesses with multiple workers in similar roles, getting the classification right for one worker effectively sets the standard for all of them. This is worth addressing proactively rather than waiting for an audit.