| name | bankruptcy-interest-calculation |
| title | Bankruptcy Claim Interest Calculation |
| description | Calculates pre-petition interest for bankruptcy proofs of claim and produces a filing-ready worksheet. Covers rate source hierarchy, day-count conventions, simple interest formulas, post-petition rules under 11 U.S.C. § 506(b), and fee inclusion standards. Use when preparing interest components of a proof of claim, calculating creditor claim amounts, or verifying interest calculations. |
| author | CaseMark |
| author_url | https://github.com/CaseMark/skills/tree/main/skills/legal/bankruptcy-interest-calculation |
| license | Apache-2.0 |
| version | 0.1.0 |
| execution_mode | open |
| jurisdiction | us |
| practice | bankruptcy |
| language | en |
Bankruptcy Claim Interest Calculation
Calculates pre-petition interest and generates a defensible worksheet for attachment to a proof of claim.
Prerequisites
- Principal balance as of last payment or accrual date
- Annual interest rate and governing source (contract, judgment, or statute)
- Last payment date and petition date
- Underlying agreement (for day-count convention and fee authorization)
Quick Start
Per Diem = (Principal × Annual Rate) ÷ Day-Count Divisor
Pre-Petition Interest = Per Diem × Days (Last Payment → Petition Date)
Use the day-count divisor required by the contract or governing standard (e.g., 365 or 360).
Core Workflow
1. Determine Interest Rate
| Priority | Source | Notes |
|---|
| 1 | Contract rate | Express provision in loan agreement or note |
| 2 | Judgment rate | Rate from pre-petition judgment |
| 3 | State statutory | Applicable state prejudgment rate |
| 4 | Federal rate | 28 U.S.C. § 1961 (Treasury bill rate) |
Cite the source in the proof of claim with section number or statutory citation.
2. Select Day-Count Convention
| Convention | Divisor | Typical Use |
|---|
| Actual/365 | 365 | Consumer loans, mortgages (default if unspecified) |
| Actual/360 | 360 | Commercial loans, credit facilities |
| 30/360 | 360 (30-day months) | Bonds, commercial paper |
Follow the contract. Default to Actual/365 only when unspecified.
3. Calculate Interest
Simple interest (most common for bankruptcy claims):
Per Diem = (Principal × Annual Rate) ÷ Day-Count Divisor
Interest = Per Diem × Actual Days in Accrual Period
Total Claim = Principal + Interest + Authorized Charges
4. Apply Post-Petition Rules
| Claim Type | Post-Petition Interest? |
|---|
| Unsecured | No — stop at petition date (exception: solvent-debtor cases) |
