Utah: Prejudgment Interest Rules

The short answer

Utah runs three separate tracks for prejudgment interest, not a simple contract-
versus-tort line. A contract claim -- including a general breach-of-contract claim,
not just a loan -- draws interest at 10% a year under Utah Code section 15-1-1,
unless the contract itself sets a different rate. A personal-injury or wrongful-death
tort claim runs on its own dedicated statute, section 78B-5-824, at a floating rate
between 5% and 10%, but only on the economic "special damages" the plaintiff has
already incurred, and a smaller-value case can't claim it at all unless the plaintiff
first made a qualifying written settlement demand well before trial. Every other
claim -- most other torts -- falls back to Utah's general common-law rule: if the
damages are fixed and can be measured by facts and figures as of a particular date,
interest runs from that date at the state's general postjudgment rate; if the damages
can't be calculated with that kind of precision (the classic examples are ordinary
personal injury, wrongful death, defamation, and false imprisonment), no
prejudgment interest is available at all.

Requirements one by one

Governing law

Three different sources do the work. Utah Code § 15-1-1 sets the contract interest
rate -- broadened by a 2019 amendment to expressly reach "a claim for breach of
contract" generally, not just a loan or forbearance as it once did. Utah Code §
78B-5-824 is a dedicated statute, entirely separate from § 15-1-1, built specifically
for personal-injury and wrongful-death tort verdicts. And for everything else, Utah
courts apply a common-law "ascertainability" rule going back to Bjork v. April
Industries (1977), which borrows the rate set by § 15-1-4 (Utah's general
interest-on-judgments statute) as the prejudgment rate when the common-law test is
met.

Interest rate

10% a year by default for a contract claim under § 15-1-1, unless the parties agreed
to a different rate. For a personal-injury or wrongful-death claim under § 78B-5-824,
the rate floats: two percentage points above the prime rate published by the Federal
Reserve on the first business day of January each year, but never lower than 5% or
higher than 10%. For other ascertainable-damage claims that fall outside both of
those categories, Utah courts have applied the federal postjudgment rate plus 2%
under § 15-1-4 as the prejudgment rate too.

When interest starts running

For a contract claim, from the date the loss became fixed and ascertainable. For
personal-injury/wrongful-death special damages, from the date each item of special
damages was actually incurred -- with a January 1 reset each year for damages
incurred in a later calendar year than the underlying injury. Under the general
common-law rule, if the damage is "complete" and "can be measured by facts and
figures" as of a specific date, interest runs from that date; if it can't be
calculated with mathematical accuracy until a jury or judge fixes the number at
trial, there's no earlier date to run interest from at all -- the claim simply
doesn't draw prejudgment interest.

Contract vs. tort claims

This is genuinely a three-way split. Contract claims -- now including any breach-of-
contract claim under the 2019-amended § 15-1-1, not just a loan -- get the 10% rate.
Personal-injury and wrongful-death tort claims get their own dedicated mechanism,
§ 78B-5-824, but only on already-incurred economic damages and, for smaller cases,
only after a qualifying settlement demand. Every other tort or claim type -- a
business tort, a property-damage claim outside the personal-injury statute, a
statutory claim with no rate of its own -- falls back to the common-law
ascertainability rule: interest at § 15-1-4's rate if the damages are fixed and
calculable, nothing at all if they aren't.

Mandatory or discretionary

Once the underlying facts are established, awarding or denying prejudgment interest
is treated as a question of law reviewed for correctness, not an exercise of
discretion -- Utah's courts have said so explicitly. For personal-injury/wrongful-
death claims, § 78B-5-824 goes further and makes the award mandatory ("the court ...
shall add interest") once its own conditions are met: special damages actually
incurred, and, for smaller (tier 1) cases, a qualifying prior settlement demand.

Simple or compound

§ 78B-5-824 expressly requires simple interest for personal-injury and wrongful-
death damages. Neither § 15-1-1 nor § 15-1-4 says anything about compounding for the
contract or common-law tracks, and Utah courts computing prejudgment interest under
the ascertainability rule likewise apply simple interest.

Claims against the government

The Governmental Immunity Act of Utah caps the total judgment a court can enter
against a governmental entity, or an employee the entity has a duty to indemnify:
currently $583,900 per person for personal injury, $233,600 for property damage, and
a $3,000,000 aggregate limit per single occurrence, adjusted for inflation every
even-numbered year. Because § 78B-5-824(2) requires the court to add prejudgment
interest into the judgment and "include it in that judgment," the interest counts
toward -- and can be squeezed out entirely by -- that same per-occurrence cap, rather
than being added on top of it.

Other exceptions

§ 78B-5-824 excludes future medical expenses, future lost wages, and future lost
earning capacity from the "special damages" that draw prejudgment interest -- only
damages the plaintiff has already incurred as of judgment qualify. A tier-1
personal-injury or wrongful-death plaintiff -- generally the lower-value cases under
Utah's civil case-management rules -- can only claim this interest at all if they
tendered a written settlement demand at least 60 days before trial that turns out to
be within 133% of what the jury or court eventually awards; tier-2 and tier-3
(larger) cases are exempt from that precondition entirely.

What trips people up

Assuming a general breach-of-contract claim always qualifies for § 15-1-1's 10% rate
is only true as of the 2019 amendment -- older cases construing the statute (USA
Power v. PacifiCorp, Fuller v. Bohne) applied a narrower, pre-2019 version limited to
loans and forbearances, and that narrower reading no longer reflects the statute's
current text for a contract claim, even though those cases' separate holding that a
TORT claim doesn't get § 15-1-1's rate is still good law.

Assuming any personal-injury claim automatically draws prejudgment interest is a
second trap: § 78B-5-824 only reaches special damages already incurred (not future
medical or wage-loss damages), and a smaller (tier 1) case needs a qualifying
settlement demand first -- something plaintiffs' counsel can miss if they don't
tender the demand early enough.

Assuming Utah's "postjudgment interest" statute, § 15-1-4, only applies after
judgment is entered is a third trap -- Utah courts have applied its rate as the
PREjudgment rate too, for ascertainable-damage claims (including some torts) outside
the personal-injury statute's coverage, running all the way back to the date of the
loss.

Common questions

What's Utah's prejudgment interest rate?
10% a year for a contract claim under § 15-1-1 (or the contract's own rate); a
floating 5%-10% rate for a personal-injury or wrongful-death tort claim under §
78B-5-824; the federal postjudgment rate plus 2% for other ascertainable-damage
claims.

Can I get prejudgment interest on a Utah personal injury claim?
Only on economic damages you've already incurred (not future medical expenses or
lost future wages), and only if your case is smaller-value (tier 1) and you tendered
a qualifying written settlement demand at least 60 days before trial. Larger cases
don't need that settlement-demand step.

Does Utah prejudgment interest compound?
Not for personal-injury/wrongful-death claims -- § 78B-5-824 requires simple
interest. The contract and common-law tracks are computed as simple interest in
practice as well; no Utah statute calls for compounding.

Can I get prejudgment interest against a Utah state or local government entity?
Yes, but the interest is folded into, and capped by, the same per-occurrence damage
limit the Governmental Immunity Act sets for the underlying judgment -- currently
$583,900 per person for personal injury and $233,600 for property damage, adjusted
periodically for inflation.

Statutes and sources

• Utah Code § 15-1-1 -- "the legal rate of interest for the contract, including a
  contract for services, a loan or forbearance of any money, goods, or services, or a
  claim for breach of contract is 10% per annum." Accessed 2026-07-05:
  https://le.utah.gov/xcode/Title15/Chapter1/C15-1_1800010118000101.pdf
• Fuller v. Bohne, 2017 UT App 28 -- holds a tort claim uses § 15-1-4's rate, not
  § 15-1-1's, applying the pre-2019 version of § 15-1-1. Accessed 2026-07-05:
  https://www.courtlistener.com/opinion/5309964/
• Bjork v. April Industries, Inc., 560 P.2d 315, 317 (Utah 1977) -- the
  ascertainability rule, quoted in Kraatz v. Heritage Imports, 2003 UT App 201, ¶
  64. Accessed 2026-07-05:
  https://law.justia.com/cases/utah/court-of-appeals-published/2003/kraatz061203.html
• Utah Code § 78B-5-824 -- the personal-injury/wrongful-death prejudgment interest
  statute: simple interest, a 5%-10% floating rate, and the tier-1 settlement-demand
  gate. Accessed 2026-07-05:
  https://le.utah.gov/xcode/Title78B/Chapter5/C78B-5-S824_2014040320140513.pdf
• Utah Code § 15-1-4(3)(a) -- the federal postjudgment rate plus 2%, applied by
  courts as a prejudgment rate for other ascertainable-damage claims. Accessed
  2026-07-05: https://le.utah.gov/xcode/Title15/Chapter1/C15-1_1800010118000101.pdf
• Utah Code § 63G-7-604 -- the Governmental Immunity Act's per-occurrence damage
  caps. Accessed 2026-07-05:
  https://codes.findlaw.com/ut/title-63g-general-government/ut-code-sect-63g-7-604/