MosoFin skill · payroll-clearing-reconciliation · learning guide

From one pay run to what is stuck in payroll clearing

This page shows how the skill finds the money that stays in a payroll clearing account, one level at a time. It starts with one pay run that returns to nil. It ends with the clean-up proposals for every item that did not. 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 section of an OpenStax textbook, two IRS pages, two pages from the California State Controller and an HMRC 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 the movements of your own clearing account and your liabilities. The page ages them and tests their behaviour. It has no tax rate field.
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 continue the payroll reconciliation example. The company is the same made-up Northbrook Trading, with its books in US dollars on the accrual basis. The period is September 2026, the last month of the quarter that the other page reconciles. The as-at date is Wednesday 30 September 2026. The owner runs the skill on Monday 19 October 2026. Every tax amount comes from the payroll provider's report for Northbrook. This page uses no tax rate.

Northbrook's answers to the eight intake questions
  1. Use MosoFin, or upload the data? Northbrook uploads the data. Level 4 and part 2 of the calculator show what changes on the MosoFin path.
  2. Which entity, and which payroll accounts? Northbrook Trading only. The accounts are 2200 Payroll clearing (net pay), 2210 Federal payroll taxes payable, 2230 401(k) payable and 2240 State unemployment payable. The chart has no suspense account and no garnishment account. The skill finds payroll movement on 2250 Accrued payroll ($2,500 at 30 September), which is not on the list. It flags 2250 as a scope gap. The owner reviews 2250 with the month-end accruals, so the workpaper names it as excluded, with that reason.
  3. Which period? September 2026.
  4. The remittance cadence of each liability. Federal taxes each month, by the 15th of the next month, or the next business day after a weekend or holiday. The 401(k) money each month, by the 7th of the next month, under the plan. State unemployment each quarter, by the end of the month after the quarter. Net pay clears on each pay date. The owner gives all of these. The skill supplies none of them.
  5. The payroll register. The provider's register for September: the bonus run on 15 September and the monthly run on 30 September.
  6. The bank statement. The statement for September.
  7. The materiality threshold, and who approves a write-off. $50.00, and the owner approves each write-off.
  8. The statements of account. Northbrook has none yet. Level 6 asks for the state unemployment statement, because of 2240.

The uploads are the GL detail of the four accounts, from 1 October 2025 to 30 September 2026. They also include trial balances at 31 August and 30 September, the register, the remittance records and the bank statement. This is the first run. The workpaper says: “Opening agreed to prior reconciliation: N, no prior reconciliation. Opening taken from the 31 August trial balance.”

The card's own read-back sample is a UK one, with PAYE on the 22nd. For this US example, the skill reads back the scope and waits for a yes:

“Reconciling the payroll control accounts of Northbrook Trading for September 2026: payroll clearing 2200, federal payroll taxes 2210, 401(k) 2230 and state unemployment 2240. I use the files you uploaded. They are the GL detail for the last twelve months, and trial balances at 31 August and 30 September. They also include the September payroll register, the remittance records and the September bank statement. The accrual side uses the register. Federal taxes remitted monthly by the 15th, 401(k) monthly by the 7th, state unemployment quarterly. The bank tie-out is to the bank statement. Shall I go ahead?”

The read-back never repeats the line of one employee.

Learning path

Six levels, from simple to complex

Check it yourself

Find what is stuck in your clearing account

Enter the movements of your own clearing account, or load an example. The page runs the arithmetic of Step 0b and Step 7 from references/method.md. Part 2 tests the behaviour of up to four liabilities. The page has no tax rate field and calculates no penalty. It sends nothing anywhere.

Part 1 · The clearing account

The account
The opening balance

Enter only the movements that did not return to nil. A normal pay run credits the account and the payout debits it on the same day, so you can omit it. A plus amount goes into the account. A minus amount leaves it.

DateAmountReferenceType

Part 2 · Liability behaviour

LiabilityOpeningAccruedRemittedGL closingOne period's accrual

The page sorts the movements by date. A minus amount first settles the item with the same reference. Without a match, it settles the oldest item first (FIFO). The bands count whole months from the month of the item to the as-at month. Days count calendar days to the as-at date. “One period's accrual” is what the cadence says the account should carry at the period end. A result from this page is a proposal. A person decides and posts each entry.

Using it

What it asks, needs and gives back

Asks firstEight things, in one message. Use MosoFin, or upload the data? Which entity and which payroll accounts? Which period? The remittance cadence of each liability. Then the payroll register, the bank statement, your write-off threshold and its approver, and any statements of account.
NeedsThe GL detail of each payroll account for the period and the prior twelve months, and the balances at both period ends. It also needs the register and the remittance records. It recommends the bank statement, the provider statements and the prior reconciliation.
Gives backNine tabs: one for each account, the master summary, the bank tie-out, the proposed entries, the stale balances and the coverage sheet. It makes the Excel file only on a yes, for example Payroll_Recs_2026-09_Northbrook Trading.xlsx.
NeverThe skill never reads your data before your yes to the read-back. It never writes, posts or pays, and never names a person or shows the pay of one. It never writes off the pay that a person did not get, and never guesses a cadence, a write-off or an escheatment treatment. It never saves a balance or an ageing.

The full tie-out of the register to the books and the bank belongs to payroll reconciliation. The skill sends the entries to journal-entry-builder. The payroll journal itself belongs to payroll-journal-entry-builder.

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 section of an OpenStax textbook, two IRS pages, two pages from the California State Controller's Office and an HMRC 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 ageing bands, the 60-day threshold and the rule of one cycle plus its due-date lag are the skill's own. So are the lowest running balance as the residual, the table of nine causes, the [auto], [gated] and [manual] verdicts and the workpaper tabs. MosoFin made up Northbrook Trading and every figure in the examples. This page states no tax rate, no wage cap and no escheatment period for Northbrook. Every tax amount comes from Northbrook's payroll provider report. The California rules are the example of one state only.