MosoFin skill · cash-application · learning guide

From one payment to every invoice it settles

This page shows how the skill applies customer payments to open invoices, one level at a time. It starts with one payment that names its invoice. It ends with the things that the skill must not do. The page quotes every rule from the skill and works every number in front of you.

The rules are the skill's ownThe page quotes each rule word for word, with the file and section it comes from.

Outside sources back the factsThey are a Federal Reserve service page, three sections of an OpenStax textbook, the IFRS standard IAS 21 and an IRS page. Each one has a number and a link.

The page shows the mathOpen "Check it yourself" on any level. Follow every line on a calculator.

Your numbers, your checkAt the end, enter one short or extra payment of your own. The page shows its treatment and the draft entry, and it runs the tie-out.

Rule: quoted from the skill Fact: from a cited authority, numbered like ¹ Example: made-up figures, calculated in full

How it thinks

Twelve rules the whole skill runs on

Every level below applies one or more of these rules. The examples use one made-up company, Northbrook Trading, which keeps its books in US dollars on the accrual basis. The customers and invoices continue from the A/R aging page, which uses Wednesday 30 September 2026 as its date.

The example

Six payments into Northbrook, 1 to 9 October

On Friday 9 October 2026, the owner uploads the bank's deposit listing for Thursday 1 to Friday 9 October. The owner did not enter these payments in the books yet. The owner chooses MosoFin as the data source.

The intake answers, A to G

AMosoFin. BA file that is not entered yet. Open invoices as of Friday 9 October. CTwo remittances: a PDF from Crestline Foods and an email from Lakeside Freight. DA tolerance of $5 for each payment. The skill does not say if the tolerance is for each payment or for each invoice, so the unit is this example's choice. EOldest invoice first (FIFO). The owner chooses this order. FAll payments are in US dollars. No currency differs, so Step 5 does not apply. GNo customer withholds tax.

Then the skill reads the plan back and waits for a yes. The card's own example uses a 14 October lockbox file with 38 payments. For Northbrook, this page's version reads like this:

Applying the 1 to 9 October deposit listing you uploaded, 6 payments for $58,997.00, to Northbrook Trading's open invoices as of 9 October. The invoices come from your MosoFin connection. Tolerance $5 per payment, oldest invoice first, remittances for 2 of the payments. Shall I go ahead?

The open invoices on Friday 9 October

The skill reads the full aging, with no date limit, and states that window. Pinnacle Clinics paid INV-1010 on Thursday 8 October, so that invoice is not open. Two invoices are new since 30 September.

Customer	Item	Dated	Due	Open	Note
Harbor Retail	INV-0950	—	Sat 1 Aug	$8,500.00	—
Harbor Retail	INV-1001	—	Tue 15 Sep	$12,000.00	—
Crestline Foods	INV-0901	Thu 21 May	Sat 20 Jun	$6,400.00	original $10,000.00, terms 2/10, n/30
Crestline Foods	INV-1035	Mon 5 Oct	Wed 4 Nov	$3,300.00	new, net 30
Summit Hotels	INV-0870	—	Fri 1 May	$15,000.00	insolvency notice
Acme Corp	INV-0990	—	Mon 31 Aug	$3,300.00	disputed
Lakeside Freight	INV-1032	Thu 1 Oct	Sat 31 Oct	$5,000.00	new, net 30
Lakeside Freight	CM-0044	—	—	−$1,200.00	credit memo, not applied
Net open A/R				$52,300.00	gross $53,500.00

Gross: 8,500 + 12,000 + 6,400 + 3,300 + 15,000 + 3,300 + 5,000 = 53,500. Less CM-0044 of 1,200, net is 52,300. Check from the A/R aging page: 69,400 − 24,200 (Pinnacle, paid) + 5,000 + 3,300 (new) = 53,500.

The deposit listing

Row	Date	Bank string	Method	Amount	Reference or remittance
P1	Fri 2 Oct	HARBOR RETAIL GRP	ACH	$20,500.00	none
P2	Mon 5 Oct	CRESTLINE FOODS LLC	cheque	$6,272.00	"INV-0901 6,400.00 less 2% prompt-payment discount 128.00"
P3	Tue 6 Oct	LAKESIDE FRT INC	wire	$3,775.00	ref INV-1032. "INV-1032 5,000.00 less CM-0044 1,200.00 = 3,800.00"
P4	Wed 7 Oct	ACH CREDIT 4471	ACH	$3,300.00	none
P5	Thu 8 Oct	PINNACLE CLINICS	wire	$24,200.00	ref INV-1010
P6	Fri 9 Oct	J MORALES	ACH	$950.00	none
File total				$58,997.00	6 payments

20,500 + 6,272 + 3,775 + 3,300 + 24,200 + 950 = 58,997. The remittance text in quotation marks is the customer's note. MosoFin made it up for this example.

Learning path

Six levels, from simple to complex

Check it yourself

Put in your own payment

Part 1 runs Step 3 from references/method.md on one payment and one invoice. Part 2 runs the control tie-out from Step 7. The page sends nothing anywhere.

Part 1: Short or over pay: what happens to the difference

The invoice and the payment Invoice open balance Amount received Credit memo applied (optional) Amount sent, from the remittance (optional) Tolerance, an amount (blank = none)

The reason Reason the customer gives Invoice date (discount) Discount, % Discount days Payment date

The page takes the credit memo off the open balance first. The residual is that balance minus the amount received. A positive residual is a short pay, and a negative residual is an over pay. Like the skill, the page tests the residual against the tolerance before it looks at the reason. A blank tolerance means that every residual is above it. The page works out an early-pay discount on the open balance after the credit memo. Your terms can use another base. With the $150 tolerance, the Crestline example shows the order of the tests. The $128 is then inside the tolerance, so the page proposes a small-balance adjustment and does not check the late discount. Every entry here is a draft for a person to post.

Part 2: Control tie-out

The payments Total payments processed Applied to A/R Customer credit Unidentified or unapplied

The parts on their own lines Discounts Bank fees Withholding tax FX: gain +, loss −

The page uses the skill's tie-out: applied to A/R − discounts − fees − withholding tax ± FX + customer credit + unidentified. The result must equal the total payments. The preset gives a difference of $0.00. The skill shows the difference even when it is zero.

Using it

What it asks, needs and gives back

Asks firstUse MosoFin for this run, or upload the data yourself? It asks this only if the MosoFin tools are present. Which payments: ones already in the books, or a file not entered yet? As of which date for the open invoices? Do you have remittance advices, and where are they? What tolerance for short and over pays? Oldest invoice first, or another order? Any payment in another currency, at which rate, from which source? Does any customer withhold tax at source, and where?

NeedsThe skill needs the customer payments and the open invoices with their open balances. You type in the company name and the base currency. An FX rate and its source are necessary if the currencies differ. Remittance advices and a customer master make the matches stronger.

Gives backThe skill gives back five sheets: application summary, payment-to-invoice mapping, exceptions, GL posting and coverage. It asks before it makes an Excel file.

NeverThe skill never reads your data before you answer its questions and say yes to its read-back. It never writes to any system. It never picks silently or absorbs a short or over pay. It never defaults an FX rate or the entity, and it never invents a tolerance.

Sources

Where every fact on this page comes from

The rules are the skill's own. The facts below come from six outside sources. They are a Federal Reserve service page, three sections of an OpenStax textbook, the IFRS standard IAS 21 and an IRS page. MosoFin checked each one on 28 October 2026 from search results and did not open the pages. Follow the link for today's wording.

Not backed by an outside authority. The skill itself sets the six-level match hierarchy, the 0.85 similarity threshold and the short-pay reason table. It also sets the ±3-day duplicate window, the five sheets and the control tie-out. MosoFin made up Northbrook Trading, its customers and every figure in the examples. The similarity measure, the tolerance unit, the parking of P4 and the handling of Lakeside's bank string are this example's choices. The page marks them where they appear.