Loan interest and fee calculation, explained.

Why two business loans at the same bank and the same rate can owe different interest for the same quarter

From signed agreement to paid bill: where the interest check sits

1. The agreement is signed and the loan is boardedKestrel Ridge's amended agreement is signed on April 3, 2026 and entered in the loan system the same day, with twelve pricing and fee terms.
2. Rates reset and money movesTerm SOFR is read on June 29, July 30 and August 28 in the example; $1,250,000 is drawn on August 14 and $600,000 repaid on September 18.
3. Interest and fees build up every dayEach day's balance, rate and day count add a little; the quarter ends on September 30.
4. The bill is calculated and checkedTen slices of the quarter, each with its own days, balance and rate. This is where the two extra days on the term loan are caught, or sent.
5. The bill is paid, disputed or shared outThe borrower pays or questions it; banks that bought shares of a loan receive theirs and check them too.

Step 4 is the subject of this guide. The bank, borrowers, people and figures in this example are fictional.

Four facts about loan interest that catch newcomers out

Day count, accrual period, fixing, unused line fee: the four terms every loan bill uses

Fourteen terms are defined in the one-page summary.

Balance × rate × days ÷ year: the formula behind every line of a commercial loan bill

In shortEvery interest and fee line is the same four-part calculation. The hard part is choosing each input: which balance, which rate, which days, which year. A quarter with draws, repayments and resets becomes many short calculations, one for each slice in which nothing changes, added up at the end.

A federal appeals court summed up the arithmetic in one line: "interest = principal x rate x time".1 Time is the fraction of a year the money was out, and that fraction is where the conventions come in. Lenders have long used three ways to set it, which the same court listed as "the 365/365 method (exact day interest), the 360/360 method (ordinary interest) and the 365/360 method (bank interest)".1

What one quarterly bill is made of

Ten accrual periods make the bill: two for the term loan, split at the September 1 principal payment; five for the revolving loans, split at the two rate resets, the August 14 draw and the September 18 repayment; three for the unused fee, split where the drawn amount moved. Each period is rounded to the cent and the ten are added. The difference in the example sits in one of the ten: the July–August term loan line.

Five of the ten lines. The unused amount is the $15,000,000 line less $2,880,000 of loans and a $750,000 letter of credit. All figures are from the fictional example.

The July–August term loan line, worked one step at a time

The daily figure is shown rounded; the calculation carries every decimal and rounds once, at the end of the line.

Who sets the rules for a commercial loan bill, and what changed between 2020 and 2026

In shortThe loan agreement is the rule. Federal consumer billing law exempts business credit, so the market's own conventions, state contract and usury law, and the court decisions on how to read a note fill the space. Since 2020 LIBOR has ended, SOFR conventions have been written, Congress has legislated a replacement for old contracts, and in April 2026 the model risk guidance changed.

Actual/360, Actual/365 and 30/360: what each day count does to the same balance

In shortActual/360 charges for every calendar day but divides the yearly rate by 360, so a year costs 365/360 of the stated rate. Actual/365 charges exactly the stated rate. 30/360 treats every month as 30 days, so a year also costs exactly the stated rate, but a 31-day month costs the same as a 30-day one. Over a year two of the three agree; month by month all three differ.

On $10 million at 6.20%, Actual/360 costs $8,611.11 a year more than Actual/365, and $10,333.33 more in a leap year. That is the "about 1.4%" that borrowers have sued over: 365 ÷ 360 is 1.01389. Banks call it ordinary practice, and it is: the ARRC recommends Actual/360 for SOFR loans because it "is the standard convention in US money markets", while noting that other day counts are possible and that sterling loans count 365 days.3,4

Month by month, the three methods split apart

That is the Kestrel Ridge bill in miniature. The term loan's clause says "a 360-day year consisting of twelve 30-day months", so July and August count 30 days each. The system counted 31 and 31. The same mistake reached back into the second quarter:

The second-quarter day falls before the June 1 principal payment, so it is charged on the higher balance.

The 365/360 lawsuits: what Ohio, Illinois and the Eighth Circuit decided about "per annum"

In shortBetween 2011 and 2013, borrowers brought class actions arguing that a rate stated "per annum" means a 365-day year, so Actual/360 overcharged them. Appeals courts in Illinois, the Eighth Circuit and the Ohio Supreme Court read the notes as a whole and sided with the banks where the note stated the 365/360 method. The lesson for servicers runs both ways: the words in the note decide, and the system has to bill what the words say.

The clause that was tested

The borrower in Kreisler argued that "per annum" in the variable-rate clause meant twelve calendar months, so the bank had charged "101.389% of the agreed upon interest rate". The Eighth Circuit disagreed: "per annum" appeared only in the definition of the bank's prime rate, and the payment clause "clearly sets out the time factor and the method for calculating interest, which the Bank followed."1 The court added that the clause "may have been clearer had it stated that the 'annual interest,' rather than the 'interest rate,' is calculated on a 365/360 basis".1

In JNT Properties, the trial court had granted summary judgment to the bank, and the court of appeals reversed, finding the note ambiguous. The Ohio Supreme Court reinstated judgment for the bank: the "inartful use of the term 'annual interest rate'" did not make the clause ambiguous, because a reasonable reader would understand the note to define the method of computation.2 A later Ohio appeals decision applied JNT to undo a class certification: once similar notes are not ambiguous as a matter of law, there is no common question to try.14

What the cases mean for a bill

The decisions date from 2011 to 2013. Our searches found no later appellate ruling that changes them. The outcome in any case depends on the note's exact wording and the state's contract law.

Term SOFR, daily simple SOFR and compounded SOFR in arrears: when the rate is known and how it builds up

In shortTerm SOFR is read before the period starts and held for the whole period, like LIBOR was. Daily simple and daily compounded SOFR are read every day during the period, so the rate for the period is known only at the end. A lookback shifts each day's reading a few business days earlier so the bill can be ready on time. Each choice changes the arithmetic a checker has to rebuild.

Lookback, observation shift, payment delay

With SOFR in arrears, the last day's rate is published the morning after the period ends. To bill on time, agreements use a lookback: each day of the period takes the rate from a few business days earlier. The ARRC's own example is a five business day lookback, in which a loan starting June 1 takes the May 25 rate, and the bank knows every rate by June 23 for a period that ends June 30.3

The ARRC recommends a lookback "with no observation shift" for syndicated loans. An observation shift also moves the day weights to the earlier dates, and the ARRC found it "could result in a borrower paying too much or too little interest if the loan is prepaid in a period" when the two calendars have different numbers of days.3 Agreements can buy time in other ways too, such as a payment delay or a lockout that freezes the rate for the last few days. Whichever the agreement picks has to be rebuilt exactly.

Daily simple SOFR over a weekend, worked

Illustrative rates. Friday's rate covers Saturday and Sunday because SOFR is not published on weekends. A checker who weights Friday's rate for one day instead of three, or looks for a Saturday rate that does not exist, gets a different bill. The ARRC says simple and compounded interest usually differ by "a few basis points or less".3

Fixing dates, borrowing notices and the bond-market calendar behind every Term SOFR period

In shortA Term SOFR loan reads its rate two U.S. Government Securities Business Days before the period starts. That calendar belongs to the bond market, so it is close to the bank's own holiday calendar and different from it. Reading the rate on the wrong day gives a perfectly real rate for the wrong day, which is why fixing-date errors survive a casual review.

The ARRC recommends that the calendar in the agreement be "US Government Securities Business Days", any day except a weekend or a day on which the Securities Industry and Financial Markets Association recommends that its members' fixed income departments close for the whole day. SOFR, and so Term SOFR, is not published on a full-close day.4

The borrowing notice is three of those days before the period, "similar to the LIBOR convention today".4 If a rate is missing on the day, the ARRC's suggested fallback takes the rate from the first preceding business day, no more than three business days back.4

In the example's billing run, one loan's September period used the fixing published on September 1, the first day of the period, instead of August 28. The loan is a $23,842,000 term loan at Term SOFR plus a 2.10% margin, Actual/360, and September has 30 days:

No borrower complains about that. The banks that bought shares of the loan are short their part of it. Both fixings are the example's sample rates.

Rate floors and spread adjustments after LIBOR, and why floors sit idle at 2026 rates

In shortA floor sets a minimum for the benchmark; a spread adjustment adds a fixed amount to SOFR to make up for its being lower than LIBOR was. For new loans the ARRC says the floor applies to the SOFR rate itself; for old LIBOR loans that fell back to SOFR it applies to SOFR plus the adjustment. With SOFR near 3.7% in 2026, floors of 0% or 0.50% do not bite, but the clause still has to be read right for the day they do.

Real rates, for scale: SOFR was 3.62% on September 16, 2026 and 3.85% the next day, after the Federal Reserve's September move; the prime rate went from 6.75% to 7.00% on September 17.15,10 The example's sample Term SOFR fixings, 3.79% to 4.12%, are the product of a fictional rate history and are used only inside the example.

How a floor is applied

The spread adjustments

The adjustments are the five-year median gap between LIBOR and SOFR, fixed on March 5, 2021.4,16 New loans priced on SOFR often carried an adjustment of their own while the market moved off LIBOR.

In 100 credit agreements LexisNexis reviewed from May to mid-October 2022, none used the ARRC's tenor-based values as such, 13 used some tenor-based adjustment, 8 had none, and "most deals analyzed used a flat credit spread adjustment of 0.10%"; the benchmark floor "typically is 0%".17 We found no published count for 2025 or 2026. Whatever the deal chose, it is one more line in the rate build: fixing, plus any adjustment, floored as the agreement says, plus the margin.

Unused line, letter of credit, fronting and agency fees: the base each one is charged on

In shortA commercial loan's fees use the same arithmetic as its interest, on a different base. The unused line fee is charged on the commitment less whatever the agreement counts as used. The letter of credit fee is charged on the amount that could be drawn under each letter. The rate is rarely disputed; the base is, because it depends on definitions and on the day each transaction lands.

Kestrel Ridge's unused line fee for the third quarter, band by band

Kestrel Ridge's line is $15,000,000, its fee 0.30% a year on the daily unused amount, and the agreement counts loans and letters of credit as used. A standby letter of credit of $750,000 was outstanding all quarter. Each time the loans changed, the unused amount changed, so the quarter splits into three bands:

Leave the letter of credit out and the fee rises by $750,000 × 0.30% × 92 ÷ 360 = $575.00 for the quarter. In the same fictional run another borrower's fee had been charged on its line less loans only, though its agreement counted $2,400,000 of letters of credit as usage: $2,400,000 × 0.50% × 92 ÷ 360 = $3,066.67 too much. The letters had been moved to a separate account when the facility was amended.

Why the undrawn half matters

The 2025 review counted $6,911.4 billion of commitments to 6,857 borrowers, $3,362.4 billion of it drawn.21 Regulators treat an unused commitment as an exposure in its own right: the Call Report counts "Commitments for which the bank has charged a commitment fee or other consideration", "regardless of whether they contain 'material adverse change' clauses".22 The fee is the price of that exposure, and a base that is wrong by one letter of credit is wrong every day the letter is outstanding.

Default interest and late charges: the day they start, the day they stop, and the state limits on both

In shortDefault interest is the ordinary arithmetic with a higher rate, most often 2% a year above the normal rate. What decides the charge is the count of days: when the higher rate starts (on the default, on notice, or when the lender elects) and when it stops (cure, waiver, payment). Late charges turn on the grace period. State law can strike either one, and California courts have struck charges measured on the whole loan balance.

The common formulation in filed agreements adds two points: "a rate per annum equal to two percent (2%) in excess of the rate otherwise applicable thereto", or "the interest rate (including any Applicable Rate) otherwise applicable to such Loan plus 2% per annum".23

The start is where the agreements differ. Some apply the default rate automatically from the Event of Default. Some apply it from written notice, often the day after. Some leave it to the lender's election in the notice. The notices clause then decides what counts as notice: personal delivery, courier, registered mail, sometimes email to a named address, and when each is deemed given.

One default, two start dates

The borrower asked for every dollar back. It was right about the email and wrong about the rest: a covenant default continues until it is cured, waived or amended away, and a borrower can be current on every payment while its fixed charge coverage is below the agreement's minimum. A yes-or-no answer would either refund money the bank was owed or refuse a credit the borrower was owed. The arithmetic gives the answer:

The stop date matters as much. In the same fictional run, a vineyard's default was waived effective September 25, and its agreement stops the default rate when a default is "cured or waived". The loan system left it running to September 30: $1,912,500 × 2.00% × 5 ÷ 360 = $531.25 too much.

Late charges turn on the grace period in the same way. A freight company's agreement charges 5% of an installment "not received within 10 days after its due date"; the September 1 installment of $17,300.00 arrived September 9, and the system, set up with no grace period, charged $865.00 anyway.

Where the law limits the charge

A summary for orientation; take legal advice on your own loans. Which state's law applies depends on the agreement's choice of law and on who the lender is.

Splitting a quarter at every draw, repayment, reset and pricing change, then rounding as the agreement says

In shortA quarter is billed as a string of accrual periods, each with one balance and one rate. A new one starts whenever money moves, a benchmark resets, a margin steps after a compliance certificate, or a prime-based rate changes. Then each period is rounded the way the agreement or the bank's written rule says. Getting either step wrong moves the bill by dollars, and by more on large loans.

Four events that start a new period

A real split in the third quarter of 2026

The prime rate rose from 6.75% to 7.00% on September 17, 2026.10 Take an illustrative $1,000,000 loan at prime plus 1.00%, Actual/360, whose rate adjusts on the day prime changes. The quarter splits into two accrual periods:

Real figures for the prime rate; an illustrative loan.

Rounding to the cent: once per accrual period or once per bill

The ARRC recommends that SOFR rates be "rounded (not truncated) to 5 decimal points and dollar amounts be rounded to 2 decimal points" on invoices and reports, with no rounding inside the calculation itself.3

Rounding each accrual period to the cent and rounding once per bill give different totals, a cent or two each time, which is enough to make a reconciliation fail. When the agreement is silent, the bank's own written rule decides, and the check has to use the same one or every bill will show a false difference.

Agency notices and participant shares: checking what the administering bank says each lender is owed

In shortIn a shared loan, one bank administers the facility: it sets the rate, collects the interest and pays each lender its share. Each lender is owed interest on its share for each day it held it. A share bought mid-period earns the new percentage only from the recorded effective date. Lenders that check the administering bank's notices against the agreement catch short payments; those that do not, rarely do.

The ARRC's convention is the market's: "daily accrued interest is calculated on each lender's share of principal that day", and a lender that sells out "is owed interest based on the time they held part of the loan".3 Examiners expect the buyer of a participation to keep watching: "During the life of the participation, the participant should monitor the servicing and the status of the loan."25

A share that changed mid-month, worked

In the example's inbox, a bank that bought an extra 2.5% of an apartment loan wrote that its share was now 22.5% and asked for $1,030.15 more of September's $41,206.18 of interest, which is 2.5% of the whole month. The assignment was recorded effective September 15, so the month splits at that date. September's interest accrues evenly over its 30 days:

The participant was right about the share and wrong about the dates.

Nine ways a commercial loan bill goes wrong, and the document where each one starts

In shortAlmost every billing error is a set-up error: a term keyed differently from the agreement, a default left in place, an event that never reached the system. Each produces the same wrong figure every period until someone recalculates. The example's billing run shows seven of them in one morning.

Interest errors that reached courts and regulators, from Anglo Irish Bank's borrowers to Revlon's lenders

In shortInterest calculation errors do reach the record, and when they do they are large because they repeat. A misread interest term at one Irish bank touched 6,435 borrowers. A US consumer regulator found improper interest and fees across millions of auto loans. In a survey run by a calculation software vendor, more than two-thirds of the lending and fintech organizations that answered said they see payment discrepancies every week or month. No public source counts commercial billing errors in the US.

What lenders say about their own calculations

The same survey found "more than two-thirds of organizations experience loan payment discrepancies weekly or monthly", that 60% struggle to keep their systems in line with rule changes, and that 44% rate their confidence in their systems at only one or two.30,31

It was run by a company that sells calculation software; its respondents came from banks, credit unions, mortgage, auto finance and fintech lenders, and nearly a quarter worked for loan software vendors, with no split for commercial lending.31 Treat it as a sign of the problem and measure your own book.

What a wrong bill puts at risk: refunds, the borrower's trust, participant claims and exam findings

In shortAn overbill is paid back with an apology; a repeated one costs the relationship and, if it spreads across a book, a remediation program. An underbill is lost income for the bank and for every participant. Both weaken the bank's position in a dispute, because the bank's defense is that it billed what the document says.

$2.96 trillion of business loans and $6.9 trillion of shared credits, billed on floating rates with no public error count

In shortUS banks held $2,959 billion of commercial and industrial loans in September 2026. Shared National Credits, the largest syndicated facilities, reached $6.9 trillion of commitments in 2025, up 43% in six years. Most of that money is billed on floating rates with the conventions described above. Nobody publishes how often those bills are wrong.

Commercial and industrial loans at all US commercial banks were $2,958.98 billion in September 2026, seasonally adjusted.32 The Shared National Credit review covers loans of $100 million or more shared by several regulated lenders: 6,857 borrowers and 11,952 facilities in 2025, with $6,911.4 billion committed and $3,362.4 billion drawn.21,33 Behind those totals are thousands of smaller bilateral loans at community and regional banks, each with its own agreement and its own set-up.

Recalculating a loan bill is exact arithmetic; reading the agreement is where AI helps and where its output must cite the clause

In shortRecalculating a bill is arithmetic, and software can do it exactly for every bill in a run. The harder part is reading the terms out of the agreement and its amendments, which is where AI reading tools help and where their output has to show the clause it came from. Deciding whether to rebill, credit, answer a dispute or change a system set-up stays with people.

The April 2026 model guidance helps sort the pieces. A deterministic recalculation is outside its definition of a model. An AI reader of agreements is outside its scope, so the bank's own governance applies, as SR 26-2 says it should "for any tools, processes, or systems not covered".9 In practice that means evidence for every term read, a person signing every letter and credit, and a test on the bank's own agreements before trusting the reader on new ones.

A commercial loan billing dispute handled by hand today: the borrower's letter, the analyst's spreadsheet and the officer's signature

In shortMost banks send what the loan system computes and investigate when a borrower or participant complains. Then a billing analyst gathers the agreement, its amendments, the rate history and the transactions, rebuilds the period in a spreadsheet, finds the cause, and hands the answer to a servicing officer to sign. One dispute can take most of a working day.

The five people around a disputed bill

From the controller's letter to a signed answer, hand-off by hand-off

Where a day of rebuilding one bill goes

Trust the system, keep shadow spreadsheets, outsource, or recalculate every bill

Two extra days on a 30/360 term loan, caught before the send: the Kestrel Ridge Foods bill from recalculation to signed correction

In shortThis is the example from the top of the page, inside the product. Six agents recalculate all 412 bills of Tallowmere Bank's third-quarter run from their agreements before the send. Seven differ and are held. Renée Castillo, the loan servicing officer, opens the largest as a receipt, sees the clause and the arithmetic behind the wrong line, proves the cause by replaying the system's set-up, and signs the correction. Gail Sorensen co-signs because the credit is above $2,500.

1

All 412 bills, recalculated before they go out

Between 9:09 and 9:12 a.m. on Thursday, October 1, the agents recalculate every bill the core loan system printed that morning, each from its own agreement and the published rates. 405 agree within the $1.00 tolerance and are ready for the 4:00 p.m. send. Seven differ: $10,354.30 overbilled on six bills, $412.66 underbilled on one.

Each held bill carries its cause in plain words: day count, unused fee base, margin step-down, late charge, default interest, fixing date. Marcus Feld, the billing analyst, can send the 405 that agree with one confirmation.

2

The bill as a receipt, line by line

Renée opens Kestrel Ridge Foods, Loan 4471. The bill prints as a recalculation receipt: every accrual period with its days, balance, rate, basis, the recalculated amount, what the system billed and the difference. The August 14 draw, the September 1 amortization and the September 18 repayment sit on their own lines where they change the balance.

Each line carries chips for its clause, such as §2.4(c), and for the Term SOFR fixing behind it. One line is red: the term loan, July 1 to August 31, $2,691.55 over.

3

One line, with its clause and its arithmetic

She clicks the red line. Section 2.4(c) of the amended and restated agreement, page 32: "Interest on the Term Loan shall be computed on the basis of a 360-day year consisting of twelve 30-day months." Below it, the arithmetic written out both ways.

Recalculated: 7,814,177.42 × 6.20% × 60 ÷ 360 = 80,746.50. Billed by the core system: the same balance and rate × 62 ÷ 360 = 83,438.05. The rate and the balance agree; only the days differ.

4

The cause, proven by replaying the system's set-up

Renée switches on "Replay as the system billed". The receipt re-runs with the core system's day count on the term loan, Actual/360, which the bank calls 365/360. The line moves to 62 days and the difference falls to $0.00 on every line: the replay reproduces the bill to the cent, $186,904.10.

Nothing else on the bill differs, so the cause is proven. The same set-up overbilled the second quarter by $1,378.07, already paid on July 1.

5

The correction, two signatures, and the set-up fixed

The drafter prepares the corrected statement and the letter to Tessa Lindqvist, the borrower's controller: the third quarter rebilled at $184,212.55, less the $1,378.07 second-quarter credit, $182,834.48 due October 15. The statement printed that morning for $186,904.10 is never sent.

The credit in all, $4,069.62, is above Renée's $2,500 limit, so after she signs, Gail Sorensen, the loan operations supervisor, co-signs and approves the day-count change on Loan 4471 and on Loan 5208, Marlowe Street Partners, the one other note among the 38 converted on April 3 that says 30/360.

The solution's design estimate is about 15 minutes to answer a disputed bill, against half a day to two days rebuilt by hand, and its design target is 100% of bills recalculated before every send. Both are to be measured on your own run.

The rest of the billing morning on screen: a wrong fixing date, an unused fee base, a missed margin step, a late charge and two disputes

In shortKestrel Ridge is one bill. These screens show the rest of the morning: the receipt's stamped total, the terms set against the system's set-up, the rate history with a wrong fixing caught, the receipts for an underbill, a fee base, a margin step and a late charge, the disputes inbox with a borrower's and a participant bank's claims answered, and the settings.

Click any screen to open it larger. The bank, borrowers, people, rates and figures are fictional.

Arithmetic by software, signatures by people: the agents behind each receipt and the $2,500 co-signing limit

In shortEach agent has one job and limits it does not cross. The calculator does arithmetic only, and the system's billed amount is never one of its inputs. A difference is explained only when replaying the system's set-up reproduces the bill. No agent sends a bill, a credit or a letter; a person signs every one.

What each agent does, and the line it never crosses

Who holds, who signs, who co-signs and who sends

Every hold, release, signature and agent step is recorded with its time. Each receipt records the agreement version, the fixings and the transactions it used, and every settings change is saved as a new rule version.

The Tallowmere Bank team and the borrower's controller in the screens

From signed agreements and published fixings to a receipt for every bill: the data the recalculation reads and the records it keeps

In shortThe solution reads what the bank already has: the agreements, the published rates, the loan system's bills and transaction history, and the disputes. It leaves behind a receipt for every bill with each line's clause and fixing, the cause of every difference, and the drafted correction or answer waiting for a signature. The core loan system stays the system of record; set-up changes are proposed, approved and applied by people.

The servicing, document and market data systems it reads from and hands back to

Roles, maker and checker, signing limits, the activity record and every rule version are kept by the platform, so audit and examiners can follow any bill from its agreement to the signature.

Refunds, unbilled interest, dispute days and a controller's patience: where wrong loan bills cost a bank money

In shortStart from your own book. No regulator or study publishes how often commercial bills are wrong, so the numbers that matter are yours: how many bills differ from their agreements, by how much, in which direction, and how long each dispute takes. A sample recalculation of one quarter answers most of it in a week or two.

Measuring your own error rate, underbills and dispute hours in a week

What a wrong bill costs beyond the dollars on it

The return on recalculating loan bills: underbills recovered, corrections never made, disputes answered from a receipt

In shortPut in your own numbers. The return comes from three places: underbills found and collected, corrections that never have to be made because the bill was right when it went out, and disputes answered in minutes. Overbills caught protect the borrower and the relationship; they are counted separately because the money was never the bank's.

Six places the return comes from, each with its formula

Put your own billing volume, error rate and hours into the return

Try three cases. A bank billing 4,000 loan periods a year with 30 disputes and the other defaults comes out about $42,000 short of an $80,000 cost: start with disputes and conversion batches only. At 18,000 bills it clears the cost by about $86,000. At 40,000 bills and 250 disputes it clears it by about $283,000. The error rate drives every line: measure it before you believe any of them.

Score your billing operation out of 16: floating-rate volume, agreements on file, boarding set-ups, disputes and sign-off

In shortPick the answer closest to your team today. Eight questions score 0 to 2; the last is for reflection. The meter adds up your score as you go, and each question says why it matters and what a strong answer sounds like.

Explore, pilot or implement: what each score asks of your servicing team

Testing loan interest calculation software on independence, day counts, SOFR lookbacks, fee bases and proof to the cent

In shortAsk every vendor the same questions, us included. The answers show whether the tool recalculates independently from the agreement or repeats your system's set-up, what it does when a rate or a term is missing, and what evidence a borrower, a participant or an examiner would see.

Test a recalculation tool on one quarter of your own bills, with known errors planted, before any bill is held

In shortMeasure first, then run the tool beside your live billing on a quarter you can check, with errors you know about, and decide on three numbers. Nothing is held or sent by the tool during the test; your current process stays in charge.

1. Recalculate 50 bills by hand from last quarter, half floating-rate with fees, and time each one. That is your baseline.
2. List what you already know: disputes and credits from the last year, conversion batches and their defaults.
3. Gather one quarter of bills, agreements, fixings and transactions for a few hundred loans, with approval to share them. Copy ten agreements and plant known differences.
4. Run in parallel for one billing cycle, with your analysts reviewing every difference the tool reports.
5. Decide with three numbers: differences found by cause, false alarms, and minutes from a dispute's arrival to a signed answer.

Five numbers to record during the parallel billing cycle

Answers on 365/360 legality, Term SOFR arithmetic, unused line fees, default interest and SR 26-2

In shortThe questions servicers, borrowers and buyers search for most, each answered on its own.