Louisiana: Prejudgment Interest Rules

The short answer

Louisiana runs on the Civil Code, not common law, and its version of
prejudgment interest -- called "legal interest" or "judicial interest" --
reflects that. Both a contract claim and a tort claim draw the same rate: a
floating figure recalculated every year from the Federal Reserve's discount
rate (7.5% for 2026). What differs is when the clock starts. A contract
debt earns interest from the day it became due. A tort claim -- what
Louisiana law calls "ex delicto" -- never starts earlier than the date the
lawsuit was actually filed, no matter how long before that the injury
happened. Interest isn't something a court has to be asked for correctly:
Louisiana's Supreme Court has held it attaches automatically by operation
of law, even when a judgment's own text gets the date wrong. Claims against
the state or a local government follow a different, lower flat rate for
the period before judgment.

Requirements one by one

Governing law

Civil Code art. 2000 governs a contract claim: when the object of an
obligation is a sum of money, delay in paying it generates interest as
damages, from the time the payment was due. A tort claim is governed
instead by La. R.S. 13:4203, a short statute providing that legal interest
attaches from the date of judicial demand on any judgment "sounding in
damages, 'ex delicto.'" Both cross-reference the same rate-setting
machinery in R.S. 13:4202 and R.S. 9:3500.

Interest rate

The rate is the same for contract and tort claims alike: Louisiana's
"judicial interest" rate, recalculated every year by the Commissioner of
Financial Institutions at 3.25 percentage points above the Federal Reserve
Board's published discount rate as of the first business day of October,
effective for the following calendar year. That produces 7.5% for calendar
year 2026 (it was 8.25% for 2025 and 8.75% for 2024). A written contract
can set its own rate instead, and that contractual rate controls.

When interest starts running

This is where contract and tort genuinely diverge. A contract claim's
interest starts on the day the money was due, exactly as Civil Code art.
2000 states. A tort claim's interest starts on the date of "judicial
demand" -- the date the lawsuit was filed -- never on the date of the
injury itself, however long the gap between the two. The Louisiana Supreme
Court reaffirmed this in December 2025: even a signed judgment that
mistakenly recites the jury-verdict date instead of the filing date doesn't
deprive the plaintiff of interest running from the true judicial-demand
date, because the interest attaches by operation of the statute, not by
what the judgment happens to say.

Contract vs. tort claims

Louisiana pairs these differently than most states in this survey: the
RATE is identical for both claim types, but the accrual TRIGGER is not. A
contract claim starts earning interest as soon as payment is overdue; a
tort claim can't start earning interest before suit is filed, even if
years passed between the injury and the lawsuit. Get the trigger date
wrong and the interest calculation is wrong regardless of the correct rate.

Mandatory or discretionary

Mandatory, not discretionary, on both sides once a claim qualifies. Civil
Code art. 2000 lets a creditor recover contract delay-damages "without
having to prove any loss." For tort claims, the Louisiana Supreme Court has
been explicit that judicial interest "attaches... as a matter of law" from
the date of judicial demand, regardless of whether a party or a judgment
specifically asks for it that way.

Simple or compound

Simple interest. Nothing in Civil Code art. 2000, R.S. 13:4202, or R.S.
13:4203 describes compounding; each provision simply fixes an annual rate
applied against the principal for the relevant period.

Claims against the government

Personal-injury and wrongful-death claims against the state or a political
subdivision follow a separate, lower rule: legal interest accrues at a flat
6% a year -- not the floating judicial rate -- starting from the date
service of the petition was requested following judicial demand, but only
until the trial judge signs the judgment. After the judgment is signed,
interest switches over to the ordinary judicial-interest rate under R.S.
9:3500 for the remaining (postjudgment) period.

Other exceptions

A written contract's own agreed interest rate always controls over the
default judicial rate for a contract claim. A separate statute, the
Louisiana Prompt Pay Statute (R.S. 9:2784), sets a much higher daily rate
(capped at 15% of the outstanding balance) for a subcontractor's claim
against a general contractor for late payment -- a narrower, different
mechanism from the general judicial-interest rule described here.

What trips people up

Assuming a tort claim's interest runs from the date of the injury is the
most common mistake -- it doesn't. Under Louisiana law, tort interest can
never start before the lawsuit was actually filed, so a long delay between
an accident and filing suit shortens, not lengthens, the interest period
compared to what an injured person might expect.

The judicial interest rate changes every calendar year, so a case that
spans several years accrues interest at a DIFFERENT rate for each year
rather than one flat rate for the whole period -- using a single year's
rate for a multi-year case understates or overstates the true total.

A judgment that recites the wrong accrual date doesn't fix the actual
interest owed -- as the Louisiana Supreme Court confirmed in Bilalis v.
Drennan, the statutory date controls regardless of a drafting error in the
judgment itself.

Common questions

What's Louisiana's current legal (prejudgment) interest rate?
7.5% per year for calendar year 2026, recalculated annually from the
Federal Reserve discount rate plus 3.25 points. This is the same rate for
both contract and tort claims.

When does interest start on a Louisiana personal injury claim?
From the date the lawsuit was filed (judicial demand), not the date of the
accident or injury.

Does Louisiana prejudgment interest compound?
No. It's simple interest, calculated at the applicable year's fixed rate
against the principal owed.

Can I get prejudgment interest against the State of Louisiana or a
parish?
Yes, but at a lower, flat 6% rate rather than the floating judicial rate,
running from when service was requested following judicial demand and only
until the judgment is signed -- after that, the ordinary judicial rate
applies.

Statutes and sources

• La. Civ. Code art. 2000 -- "When the object of the performance is a sum
  of money, damages for delay in performance are measured by the interest
  on that sum from the time it is due, at the rate agreed by the parties
  or, in the absence of agreement, at the rate of legal interest as fixed
  by R.S. 9:3500." Accessed 2026-07-05:
  https://www.legis.la.gov/legis/Law.aspx?d=109256
• La. R.S. 13:4203 -- "Legal interest shall attach from date of judicial
  demand, on all judgments, sounding in damages, 'ex delicto', which may be
  rendered by any of the courts." Accessed 2026-07-05:
  https://legis.la.gov/Legis/Law.aspx?d=77703
• La. R.S. 13:4202(B)(1) -- sets the annual judicial-interest-rate formula
  (discount rate + 3.25 points). Accessed 2026-07-05:
  https://www.legis.la.gov/legis/Law.aspx?d=77702
• La. R.S. 9:3500(B) -- defines "legal interest," including "judicial
  interest" on sums subject to judicial demand. Accessed 2026-07-05:
  https://www.legis.la.gov/legis/Law.aspx?d=285199
• La. R.S. 13:5112(C) -- "Legal interest on any claim for personal injury
  or wrongful death shall accrue at six percent per annum from the date
  service is requested following judicial demand until the judgment
  thereon is signed by the trial judge... Legal interest accruing
  subsequent to the signing of the judgment shall be at the rate fixed by
  R.S. 9:3500." Accessed 2026-07-05: https://www.legis.la.gov/legis/Law.aspx?d=77944
• Bilalis v. Drennan, No. 2025-C-00453 (La. Dec. 18, 2025) -- holds tort
  judicial interest attaches automatically from the date of judicial
  demand regardless of a judgment's own recited date. Accessed 2026-07-05:
  https://www.courtlistener.com/opinion/10761052/