Loan interest calculation software that rebuilds every bill from the agreement, before it goes out
Disputed bills answered with the math shown line by line.
See one case, screen by screen ↓Software that works out the interest and fees a loan owes for a period from its terms, its rates and its transactions. Loan Interest & Fee Calculation does it independently of your core loan system: it rebuilds every bill from the signed agreement and the published rate fixings, then sets it against what the system billed, line by line.
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Interest on a commercial loan depends on rate resets, floors, spreads, day counts, amortization, unused-line fees and default interest — and each agreement picks its own conventions. The move from LIBOR to SOFR multiplied them: Term SOFR or daily simple SOFR, the lookback, the floor and the day-count basis all vary by deal. The core loan system computes what it was set up to compute. A single set-up mistake when a loan is boarded or converted runs silently on every bill until the borrower’s controller notices.
Day count is the classic one. Where the note says 30/360 and the system bills Actual/360, every 31-day month is overbilled by a day — and borrowers have taken 365/360 billing to court, arguing the note’s wording was unclear. When a bill is disputed, a billing analyst rebuilds it in a spreadsheet: the agreement and every amendment, the rate fixings, the draws and repayments. That takes half a day to two days per dispute, and at the end nobody can easily show which term drove the number.
Estimated split, in hours, for one disputed commercial loan bill, rebuilt by hand and with the solution. Review and signature stay with the servicing officer.
Six specialist agents recalculate every bill from the agreement and the rates; the servicing officer decides and signs.
Thursday 1 October, 09:12. The Q3 billing run has printed 412 bills, due to go out at 16:00. Here is what happens next, screen by screen, in the working solution.
The agents recalculate all 412 bills the core loan system printed this morning, each from its own agreement. 405 agree within $1.00 and are ready for the 16:00 send. Seven differ: $10,354.30 overbilled on six bills, $412.66 underbilled on one. Each is held, with its cause named — day count, unused fee base, margin step-down, late charge, default interest, fixing date.
“Tolerance $1.00 per bill · a bill that differs is held from the send.”
Kestrel Ridge Foods, Inc., Loan 4471: a term loan and a $15,000,000 revolving line under an amended and restated credit agreement of 3 April 2026. Renée sees the bill as a recalculation receipt — every accrual period with its days, balance, rate, basis, recalculated amount, the system’s amount and the difference. The draw on 14 August, the amortization on 1 September and the repayment on 18 September sit on their own lines where they change the balance.
The term loan line for 1 July – 31 August is red. Renée opens it: §2.4(c) says term loan interest is computed on a 360-day year of twelve 30-day months, and the arithmetic is written out. Recalculated: 7,814,177.42 × 6.20% × 60 / 360 = 80,746.50. Core system billed: the same balance and rate × 62 / 360 = 83,438.05.
“Interest on the Term Loan shall be computed on the basis of a 360-day year consisting of twelve 30-day months.” — §2.4(c)
Ten accrual periods, rounded per period, half up, from the agreement version of 3 April 2026. The receipt also records what did not apply: the 0.50% floor was not reached (the lowest fixing was 3.86192%), there was no Event of Default in the quarter, and letter of credit SB-2207 counted as usage for the unused line fee. The stamp reads overbilled $2,691.55 — day count.
Renée switches on “Replay as the system billed”. The receipt re-runs with the core system’s 365/360 day count on the term loan: the line moves to 62 days and the difference falls to $0.00. Nothing else on the bill differs. The same set-up overbilled Q2 by $1,378.07, already paid on 1 July.
“With the system’s set-up the receipt reproduces the bill to the cent, $186,904.10. Nothing else differs — the cause is proven, not assumed.”
The loan terms screen sets every pricing and fee term from the agreement — rate, day count, amortization, Term SOFR 1-month, the fixing two U.S. Government Securities Business Days before the period, the 0.50% floor, the 2.35% Applicable Margin, the unused line fee, default interest — against the core system’s set-up, with the clause beside each. Eleven match. The term loan day count differs: 30/360 in the agreement, 365/360 (Actual/360) in the system since the loan was converted on 3 April.
Kestrel Ridge’s revolver priced off Term SOFR 1-month fixings of 4.12062% (29 June), 3.98741% (30 July) and 3.86192% (28 August), each far above the floor. The same screen shows why Ostrander Tool & Die’s bill is $412.66 too low: its September period used the 1 September fixing, 3.84115%, instead of 28 August.
From the receipt, the drafter prepares the corrected statement and the letter to Tessa Lindqvist, the borrower’s controller: Q3 rebilled at $184,212.55, less the $1,378.07 Q2 credit — $182,834.48 due 15 October. It proposes the set-up change for two loans: the agents read all 38 loans converted on 3 April, and Marlowe Street Partners LP has the same 30/360 note.
“The statement printed this morning for $186,904.10 was not sent. Credit to the borrower in all: $4,069.62 — above the $2,500 limit, so it needs a second signature.”
Renée signs the correction. Because the credit is above her $2,500 limit, it goes to Gail Sorensen, who co-signs and approves the day-count change on Loans 4471 and 5208. The corrected statement goes to Tessa Lindqvist with the recalculation enclosed, before the borrower ever had to find it.
Bellhaven Dairy Cooperative disputes $10,406.67 of default interest on its August statement. Each claim is checked against the agreement: the 11 August email was not notice under §10.1, so the default rate starts 18 August, not 11 August — but the fixed charge coverage of 1.08x against 1.20x was a continuing Event of Default. Partly right: a $3,468.89 credit, with the answer drafted for Renée’s signature.
The drafter never sends a letter or a credit. A person signs every answer.
The same billing run, seen by the four people who carry it — what their quarter looked like, and what it looks like now.
Six specialist agents recalculate every bill from the agreement and the rates; the servicing officer decides and signs.
Reads pricing and fee terms from the credit agreement and its amendments in date order — margin, index, floor, fixing date, day counts, fees, default rate, payment dates — each with its clause and page.
Works out each fixing date the agreement defines, pulls the published Term SOFR or prime fixing for it and tests the floor.
Reads draws, repayments, amortization, letters of credit and payments from the loan’s transaction history.
Splits the period wherever the balance or the rate changes and rebuilds every accrual period — days under the agreement’s day count, balance, rate with the floor applied, amount — rounded as the agreement says.
Compares the recalculation with the system bill line by line, finds the term whose set-up differs from the agreement, and replays the system’s set-up to confirm it reproduces the bill to the cent.
Reads borrower and participant disputes, lists and checks each claim against the agreement and the recalculation, and drafts the answer or the correction with the figures.
Signs; a supervisor co-signs above $2,500. The agents propose; a named person decides.
Ask about any bill, term, rate or dispute. The answer comes with the clause and the arithmetic.
Why is the Kestrel Ridge bill $2,691.55 too high?
All of it is on the term loan for 1 Jul – 31 Aug. Section 2.4(c) computes term loan interest on twelve 30-day months — 60 days, $80,746.50. The core system billed 62 actual days on a 360-day year: $83,438.05. Replaying the system’s set-up reproduces the bill to the cent, so nothing else differs. The same set-up added $1,378.07 to Q2.
Which other loans have the same day-count set-up?
One more: Marlowe Street Partners LP, Loan 5208 — the note says 30/360, the system billed 92 days instead of 90, $1,184.20 over this quarter. Both were converted on 3 Apr; all 38 notes from that batch were read and the other 36 agree with the set-up.
Is Bellhaven Dairy right about the default interest?
Partly. The email of 11 Aug was not notice — notices go by courier or registered mail — and the default rate starts the day after notice, so 18 Aug, not 11 Aug: 14 days, $6,937.78. The rest stands: coverage was 1.08x against 1.20x. Credit $3,468.89; the answer is drafted for your signature.
Draft the correction for Kestrel Ridge
Drafted. Q3 rebilled at $184,212.55 from the receipt, Q2 overbill of $1,378.07 credited, $182,834.48 due 15 Oct. The credit of $4,069.62 is above your $2,500 limit, so Gail Sorensen co-signs; the day-count change for Loans 4471 and 5208 goes to her with it.
13 screens from the working solution, on its sample data. Pick one to see it large.
How bills are recalculated, held and signed. Every change is saved as a new rule version.
| Setting | Default | Choose from |
|---|---|---|
| Tolerance before a bill is held | $1.00 per bill | $0.00 to $25.00, in $1.00 steps |
| Hold bills that differ from the send | On | On · Off |
| Recalculate before every billing run | On — 3 hours before the scheduled send | On · Off |
| Recalculate a disputed bill on arrival | On | On · Off |
| Rounding, when the agreement is silent | Per accrual period, to the cent, half up | Per accrual period · Per bill, to the cent, half up · Per day, to the cent |
| Rate sources | Published fixings only | Term SOFR 1M · Term SOFR 3M · Prime rate |
| Servicing officer signs credits up to | $2,500 | $1,000 · $2,500 · $5,000 |
| Core system set-up changes | Supervisor approval | Proposed by the agents, applied by loan operations |
Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.
“demo” = seen in the working solution, on its sample loan data · “target” = the design goal, measured in the live solution · “estimated” = our estimate · “typical” = published figures (Carleton lending survey, 2025, reported by Digital Dealer: over two-thirds of lenders report recurring loan calculation errors; 14% say their tools handle tiered or variable-rate loans well). Day-count litigation: JNT Properties v. KeyBank (Ohio Supreme Court, 2012). Term SOFR conventions: ARRC recommended conventions for syndicated loans. People, companies, banks and loans named on this page are fictional — characters and sample data in the working solution.
Software that works out the interest and fees a loan owes for a period from its terms, its rates and its transactions. Loan Interest & Fee Calculation does it independently of your core loan system: it rebuilds every bill from the signed agreement and the published rate fixings, then sets it against what the system billed, line by line.
It splits the billing period wherever the balance or the rate changes and recalculates each accrual period — days under the agreement’s day count, balance, rate and amount — rounded as the agreement says. Each line carries its clause and its rate fixing, and the bill is held if it differs from the system by more than the tolerance, $1.00 by default.
Yes. It reads the index, tenor, fixing date and floor each agreement defines — for example Term SOFR 1-month fixed two U.S. Government Securities Business Days before the period, with a 0.50% floor — and applies the agreement’s day count, such as 30/360 for a term loan and Actual/360 for revolving loans and fees. Rates come from published fixings only; a missing fixing stops the calculation.
The bill is held from the send and the difference is traced to the term that caused it. The cause counts as proven only when replaying the system’s own set-up reproduces the bill to the cent. The servicing officer then corrects and rebills, or releases it with a written reason that the supervisor sees.
Yes. A disputed bill is recalculated on arrival, each claim in the letter is checked against the agreement and the recalculation, and an answer is drafted with the figures — the bill is right, partly right, or wrong. In the working solution, a participant’s claim for $1,030.15 after an assignment is answered with $549.41 owed, shared by day from the recorded effective date.
No. When a set-up differs from the agreement, the agents propose the change; a loan operations supervisor approves it and loan operations applies it. The system’s billed interest is never used as an input to the recalculation.
Yes. The agents calculate, cite and draft; they never send a bill, a credit or a letter. The servicing officer signs, a supervisor co-signs credits above the officer’s limit — $2,500 by default — and every hold, release, signature and agent step is recorded.
The Agentic Solution Engine builds and deploys it from your requirements and documents — your agreements, servicing procedures, signing limits and a sample of past bills — and it goes live once every quality gate has passed. We can first run it on a sample of your own bills.
Booking errors caught before the first bill goes out.
1-min demoLoan Document SearchAnswers in seconds, with the clause that proves them.
1-min demoLoan Document Exception TrackingExceptions cleared in days, not left open for months, each one read before it clears.
1-min demoWe’ll recalculate a sample of your own bills from their agreements and published rates.