Prejudgment Interest Rules in Florida

At a glance

Requirements one by one

Governing law and rate

Florida’s Supreme Court stated the loss theory in Argonaut Ins. Co. v. May Plumbing Co., 474 So. 2d 212 (Fla. 1985): when a verdict fixes an out-of-pocket loss as of a prior date, interest from that loss date is generally an element of damages. Fla. Stat. § 687.01 directs interest accruing without a special contract rate to the rate in § 55.03. Section 55.03(1) uses the preceding 12-month average New York Federal Reserve discount rate plus 400 basis points, set quarterly; it expressly preserves a rate established by written contract or obligation.

When interest begins

Argonaut ties the start to the date of pecuniary loss. Bosem v. Musa Holdings, Inc., 46 So. 3d 42 (Fla. 2010), restates the rule for a pecuniary loss fixed as of a definite time, even if the amount was disputed until the court determined it. A breach date and a loss date can differ, so identify the actual economic loss before calculating.

Contract and tort treatment

Bosem explains that qualifying contract and tort losses use the same loss theory. The question is whether the loss is wholly pecuniary and can be fixed as of a definite time; the label of the lawsuit alone does not decide entitlement.

Government defendants

In Broward County v. Finlayson, 555 So. 2d 1211 (Fla. 1990), the Supreme Court allowed interest on a county back-pay award but started it at the employees’ first demand rather than at each earlier wage accrual. The court treated that timing as an equitable question on those facts.

What trips people up

Fla. Stat. § 55.03(3) fixes the rate when a judgment is obtained and adjusts that judgment rate annually on January 1 until payment. That provision concerns an entered judgment; it does not itself say that a prejudgment calculation resets every January. Section 55.03(1) and § 687.01 do not state a universal compounding method for prejudgment awards.

Finlayson also cautions that the loss-date rule is not absolute where applying it would be inequitable. Its facts involved a county’s good-faith bargaining and a back-pay demand made after the pay period.

Common questions

Must damages be undisputed before trial? No. Argonaut and Bosem allow interest after the verdict or court determines a pecuniary amount that can be assigned to an earlier loss date.

Does my written contract rate matter? Yes. Section 55.03(1) expressly preserves a written contract or obligation rate; § 687.01 provides the statutory rate where no special contract rate applies.

Statutes and sources

• Fla. Stat. § 55.03(1), (3), 2026 Florida Statutes, accessed 2026-10-06: https://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0000-0099/0055/Sections/0055.03.html
• Fla. Stat. § 687.01, 2026 Florida Statutes, accessed 2026-10-06: https://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0600-0699/0687/Sections/0687.01.html
• Argonaut Ins. Co. v. May Plumbing Co., 474 So. 2d 212 (Fla. 1985), and Bosem v. Musa Holdings, Inc., 46 So. 3d 42 (Fla. 2010), retrieved 2026-10-06.
• Broward County v. Finlayson, 555 So. 2d 1211 (Fla. 1990), retrieved 2026-10-06.