Post-judgment interest by state · Washington
Washington · after judgment
Post-judgment interest in Washington
An unpaid Washington money judgment earns 12% a year unless the judgment or a contract says otherwise. On a $5,000.00 judgment that is $600.00 in the first year, about $1.64 a day.
How the rate is set
The maximum rate under RCW 19.52.020: the higher of 12% or four percentage points above the 26-week Treasury bill yield. The 12% floor has been the rate for years; the bill yield is checked here each run.
- Statute or rule
- RCW 4.56.110(6) with RCW 19.52.020(1)
- Figure read on 2026-10-23
- 6-month Treasury bill 4.21% on 2026-10-21
- Statute re-checked
- 2026-10-23
- Changes
- higher of 12% or 6-month bill 4.21% + 4 (as of 2026-10-21)
When a different rate applies
- A consumer-debt judgment bears 9% under RCW 4.56.110(5).
- A tort judgment against a private party bears prime plus 2; against a public agency, the Treasury bill rate plus 2.
- Child support judgments bear 12%.
- A contract rate stated in the judgment governs.
Work out your own judgment
Washington is prefilled at 12%. Enter the amount and the date the judgment was entered. The calculator uses simple interest; that is how this rate accrues.
How Washington's rate is set, and where it comes from
Uses simple interest at the rate you enter — pre-filled with each state's standard statutory rate, editable since some states publish a new rate quarterly or annually. Some states apply a different rate to specific debt types (noted above where it applies) or when a contract specifies its own rate. Informational only, not legal advice; confirm the current rate and any exceptions with your court clerk before relying on this figure.
The formula, worked
Last reviewed: October 2026
Interest = principal × rate × days ÷ 365. For $5,000.00 at 12%: $5,000.00 × 0.12000 × 365 ÷ 365 = $600.00 after one year, and $1.64 for each further day.
What this page does not know
- The rate written on your judgment. If the court stated a rate, that one applies, whatever the default is today.
- Partial payments. Interest accrues only on what is still unpaid.
- Nothing about older judgments: Washington fixes the rate when the judgment is entered, so a judgment from an earlier period keeps that period's rate, not the one shown.
Informational only, not legal advice. Every figure is cited to the statute or the office that publishes it; confirm the current rate with the court clerk before relying on it.
Also for Washington: what it costs to sue in Washington small claims court.
Frequently asked questions
What is the post-judgment interest rate in Washington right now?
12% a year for an ordinary money judgment, for higher of 12% or 6-month bill 4.21% + 4 (as of 2026-10-21), under RCW 4.56.110(6) with RCW 19.52.020(1).
How is the Washington rate set?
The maximum rate under RCW 19.52.020: the higher of 12% or four percentage points above the 26-week Treasury bill yield. The 12% floor has been the rate for years; the bill yield is checked here each run.
Is it simple or compound interest?
Simple interest: it is calculated on the original judgment amount only and never on earlier interest.
Can my Washington judgment carry a different rate?
Yes. A consumer-debt judgment bears 9% under RCW 4.56.110(5). A tort judgment against a private party bears prime plus 2; against a public agency, the Treasury bill rate plus 2. Child support judgments bear 12%. A contract rate stated in the judgment governs. The judgment itself may also state a rate, and that controls.
Related tools
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