Connecticut Post-Judgment Interest Rate: How to Calculate What You're Owed

Your Judgment Can Grow While the Debtor Doesn't Pay

If a Connecticut court awards post-judgment interest, it can accrue at a court-set rate of up to 10% per annum under CGS § 37-3a. It continues accumulating until the judgment is fully satisfied, subject to the court's order or any applicable contractual rate.

At an awarded rate of 10%, a $5,000 judgment accrues $500 per year — or roughly $1.37 per day — in interest.

The Statutory Framework: CGS § 37-3a

Connecticut's post-judgment interest statute, CGS § 37-3a, allows interest on money "detained after it becomes payable." For a court judgment, money becomes payable on the date the judgment is entered. The statute permits interest at a rate of up to 10% per year.

Two situations determine the applicable rate:

Court-discretionary interest: When no contract between the parties specifies an interest rate, the court awards interest under CGS § 37-3a at its discretion — up to 10%. Many small claims judgments fall into this category (personal loans without written terms, property damage, contractor disputes).

Contractual interest: If the underlying agreement specifies an applicable post-default or post-judgment rate, that agreed rate applies under CGS § 37-1 instead of the statute's 8% default rate. A marshal may include post-judgment interest in an execution only when the court has ordered it and marked it on the form.

How to Calculate Post-Judgment Interest

The formula is straightforward:

Daily interest = (Judgment balance × Annual rate) ÷ 365

For a $3,500 judgment at 10% annual interest:

• Annual interest: $3,500 × 0.10 = $350
• Daily interest: $350 ÷ 365 = $0.96 per day
• After 6 months (180 days): $172.60 in accrued interest
• After 1 year: $350.00 in accrued interest

When calculating the judgment balance for an execution, add the accrued interest to the original judgment amount and any court costs. The $95 small claims filing fee is automatically added to the judgment at entry.

Partial payments reduce the principal balance, which in turn reduces the daily interest accrual going forward. If the debtor pays $1,000 on day 60, recalculate daily interest on the reduced balance from that date.

What Gets Added to the Judgment

The total debt the debtor owes isn't just the original judgment amount. It includes:

• Original judgment (up to $5,000 in standard small claims)
• Court filing fee ($95, added at entry)
• Post-judgment interest (if ordered by the court, accruing under CGS § 37-3a)
• State Marshal fee (15% of the execution amount under CGS § 52-261(a)(6), included in the total execution demand)
• Execution application fee ($105 for a wage, bank, or property execution; it may be recoverable as a taxable cost)

When you file an execution — whether a wage garnishment, bank levy, or property levy — include the current total with accrued interest. The court clerk and State Marshal need the correct figure to process the execution properly.

Keeping Track

Without a running ledger, it's easy to lose track of the balance — especially when partial payments come in, new enforcement costs get added, and interest accrues simultaneously. Record every payment received, every marshal fee incurred, and the running interest calculation with dates.

The Collecting a Small Claims Judgment in Connecticut guide includes a collection balance ledger designed for exactly this — tracking the judgment balance, interest accrual, partial payments, and enforcement costs in one place.

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