Tax Legal Services · Primary-source case analysis

Fior D’Italia: The IRS Could Estimate Aggregate Unreported Tips for Employer FICA Tax

By Aneeta Mishra and Timothy Chan

Published April 29, 2026 · Updated October 17, 2026

Decision: United States v. Fior D’Italia, Inc., 536 U.S. 238 (2002).

Fior D’Italia upheld the IRS’s authority to estimate a restaurant’s employer FICA liability from aggregate tips. But this restaurant had stipulated that it would not challenge the particular calculation’s accuracy. That litigation choice matters: The Court distinguished legal authority to estimate from the factual objections another taxpayer could preserve.

Reported tips were lower than charged tips

For 1991 and 1992, tips on credit-card records exceeded the employees’ reported totals. The IRS calculated average charged-tip rates of 14.49 percent and 14.29 percent, applied those rates to total receipts, and subtracted reported tips before computing added employer tax. Those were the historical assessment’s figures, not prescribed rates for other restaurants. Fior D’Italia, 536 U.S. at 241–242.

The employer tax is separate from employee assessment

The Court read the employer-tax provisions together with the tip definition and the IRS’s general assessment authority. It rejected the argument that the statutory reference to each employee required separate employee calculations before an aggregate employer assessment. The decision concerned employer FICA liability, not every tax consequence of receiving a tip. Fior D’Italia, 536 U.S. at 240–246.

Reasonable estimation is permitted

The majority discussed possible errors involving cash-tip behavior, cash returned through a card transaction, card charges and employee-specific wage limits. A taxpayer without this restaurant’s stipulation could offer evidence that the formula likely produced an inaccurate result. The Court did not require every taxpayer to accept the same percentage or promise this restaurant a new factual challenge on remand. Fior D’Italia, 536 U.S. at 246–248, 252.

Disposition

The Court reversed the Ninth Circuit on June 17, 2002. It also rejected a generalized claim that possible agency abuse made aggregate estimates unlawful in every case; the restaurant had not shown illegal conduct in its own case. Present payroll advice requires the law and records for the actual tax year. Fior D’Italia, 536 U.S. at 250–252.

Key takeaways

• Preserve point-of-sale and tip-reporting data.
• Separate employer and employee assessment rules.
• Test the sample, rate, and transaction assumptions.
• Challenge factual unreasonableness with concrete records.