# Lapping Fraud: Spotting Delayed Customer Payments

- Author: PreciseBankFlow (https://precisebankflow.com)
- Published: 2026-10-17
- Category: Embezzlement and fraud schemes
- Canonical: https://precisebankflow.com/blog/lapping-fraud

> How lapping fraud hides stolen receipts by applying later payments to older invoices, and the deposit and remittance tests that expose the pattern.
Lapping fraud is the theft of a customer payment that is then hidden by crediting the next customer's payment to the first customer's account. Each customer's balance looks only a little late, so nobody complains. The scheme shows up when you compare remittance advices and check copies with deposit slips and with the dates payments were applied.

## How does lapping fraud move one customer's payment onto another's invoice?

Lapping fraud works by delay. An employee who opens the mail or takes payments keeps one customer's check, then covers that customer's invoice with money that arrives later from someone else. The theft never disappears. It moves forward, one account to the next, for as long as fresh receipts keep coming in.

A typical sequence runs like this:

1. Customer A pays a $4,000 invoice by check. The employee endorses it to an account they control, or cashes it, and records nothing.
2. A week later Customer B pays $5,000. The employee deposits it but credits $4,000 to Customer A and only $1,000 to Customer B.
3. When Customer C pays, part of that check is used to clear what is still owed on Customer B.
4. The cycle repeats. The receivable ledger always shows some customer slightly behind, and that customer changes each time.

The general ledger cash account still agrees with the bank, because every dollar recorded as deposited really was deposited. What is wrong is the timing and the customer each deposit was credited to. That is why a bank reconciliation that balances proves nothing here on its own.

### A four-week worked example

The table is an example with invented amounts. It follows four customers through one month at a small distributor where the same clerk receives checks, prepares the deposit and posts cash to customer accounts.

| Week | Check received (example) | Amount deposited | Applied to | Shortfall carried |
| --- | --- | --- | --- | --- |
| 1 | Customer A, $4,000 | $0 | Nothing | $4,000 on A |
| 2 | Customer B, $5,000 | $5,000 | A $4,000, B $1,000 | $4,000 on B |
| 3 | Customer C, $6,500 | $6,500 | B $4,000, C $2,500 | $4,000 on C |
| 4 | Customer D, $7,000 | $7,000 | C $4,000, D $3,000 | $4,000 on D |

By week 4 the shortfall has passed through four customers, and each one looked only a week behind before the next receipt covered it. Customers have paid $22,500 and the ledger shows $18,500 received: the $4,000 taken in week 1 is still gone. The clerk now needs a new receipt every week just to stay level, and any customer who pays late breaks the chain.

## Duties that let one employee run a lapping scheme

Lapping needs one person to touch three things: the incoming payment, the deposit and the customer account posting. When one employee opens the mail, prepares the deposit and applies cash to customer accounts, they control both the money and the record that would reveal it missing. Remove any one of those duties and the scheme gets much harder.

A fourth duty makes it easier still: answering customer questions about their balance. A customer who calls to ask why a paid invoice still shows as open will reach the person who caused the problem. That person can apologize, blame a posting error and move the next receipt across before the customer calls again.

Small offices concentrate these duties for practical reasons. One bookkeeper does receivables because there is no one else. The guide to [splitting cash duties in a small business](/blog/segregation-of-duties-in-a-small-business) lays out which tasks to move to the owner or a second person when a full split is impossible.

Lapping belongs to the same family as other schemes that exploit a single unwatched role. A clerk who controls the vendor file can pay a [ghost vendor that exists only on paper](/blog/ghost-vendor-fraud), and a payroll clerk who adds and removes employees can pay a [ghost employee who never worked](/blog/ghost-employee-fraud). The fix in each case is the same idea: whoever handles the asset should not also keep its record.

## Lapping fraud traces in the customer aging and deposit timing

Lapping fraud leaves its clearest trace in the gap between when a customer paid and when the payment was credited. In the receivables aging, invoices from reliable payers slide into the 30 or 60 day column. In the bank, deposits lose their link to specific checks, and the days between receipt and deposit grow longer and less regular.

Signs to look for in the aging report:

- **Reliable customers suddenly late.** A customer who has paid in 20 days for years now shows invoices at 45 days, with no dispute on file.
- **Partial payments that are not partial.** The ledger shows a customer paying $1,000 against a $5,000 invoice, yet the customer's own records show a check for the full $5,000.
- **Credits applied to the oldest invoice first, every time, across many customers.** That habit is normal for one customer; when it covers a rolling list of accounts, it can mean receipts are being moved.
- **Unusual credit memos or small write-offs.** These sometimes appear when the scheme has to close a gap it can no longer cover.

Signs in the bank statement:

- **Deposit amounts that never match a single day's mail log.** Deposits are split, combined or held over.
- **Longer gaps between deposits.** Holding checks for a few days gives the employee room to rearrange them.
- **Deposited checks from one customer that cleared earlier than the ledger posting.** The bank's date is the truth about when money arrived.

None of these alone proves anything. Together, and concentrated on one employee's accounts, they justify the tests in the next section.

## Remittance-to-deposit tests that expose lapping

The direct test for lapping compares what each customer actually sent with what was deposited and credited, check by check. Start from source documents the employee does not control: the customer's own payment record, the bank's deposit detail and check images, and a mail log kept by someone else. Lapping cannot survive a line-by-line match between those three.

Tests in order of effort:

1. **Deposit slip to remittance match.** For a sample of deposits, list every check on the deposit slip. Match each check's payer and amount to the remittance advice and to the customer credit posted that day. Any posting to a customer other than the payer on the check is an exception.
2. **Check image to ledger credit.** Ask the bank for deposited item images for the period. The payer name on each image should match the customer credited in the ledger.
3. **Date comparison.** For each customer payment, compare the check date, the bank deposit date and the ledger posting date. Lapping widens the second gap and the third.
4. **Customer confirmations.** Send statements or confirmation requests directly to customers, mailed by someone outside receivables, and ask them to reply to that person. Customers who answer that they paid in full are the strongest evidence.
5. **Surprise cutoff.** On an unannounced day, take control of the incoming mail, list every check, and follow each one to the deposit and to the ledger.

The first three tests are matching work, and that is where software helps. PreciseBankFlow matches statement lines to the ledger and lists the deposits that do not clear against a posting, which gives you the exception list to trace by hand.

### What the results look like

A clean result has every check on a deposit slip credited to the payer named on it, on the deposit date or the next business day. A lapping result shows a pattern: payer and credited customer differ, and the difference always flows from a newer receipt to an older invoice.

## Is every late-applied customer payment a sign of lapping?

No. Late or misapplied customer payments are common and usually innocent. Customers send one check for several invoices without saying which, pay the wrong entity in a group, or deduct a disputed amount. A busy clerk may apply cash to the oldest invoice by default. The question is whether the misapplication has a pattern that favors hiding a gap.

Innocent causes and how to tell them apart:

- **Unidentified remittance.** A check arrives with no invoice number. It should sit in unapplied cash, not be spread across another customer's invoices.
- **Parent and subsidiary customers.** A group pays for several branches with one check. The payer on the image will be the parent, which matches a known relationship in the customer file.
- **Short payments for disputes or discounts.** The customer's remittance will usually explain the difference, and the open balance stays on that customer's own invoice.
- **Lockbox posting errors.** When a bank lockbox applies payments, mistakes come from the bank file, not from a person handling the check.

The distinguishing feature of lapping is direction and repetition. Honest errors scatter. Lapping moves money in one direction, from the newest receipt to the oldest unpaid item, and the account that falls behind changes from week to week.

## Why a lapping scheme keeps growing until it breaks

A lapping scheme grows because the cover must be renewed with every receipt cycle, and most people who start lapping take more than once. Each new theft adds to the amount that has to be shuffled. The shortfall stays the same only if the employee stops stealing, and even then it must be covered every week.

Events that commonly end a scheme:

- **The employee is absent.** Someone else opens the mail and posts cash directly, and several customers suddenly appear overpaid or underpaid.
- **A large customer pays late or stops buying.** There is no new receipt big enough to cover the gap.
- **A customer insists on a reconciliation of their account.** Their check copies do not match the ledger.
- **Year-end confirmations or an audit.** Customers confirm balances that differ from the books.

Some employees try to end a scheme by booking a write-off, a fake credit memo or a sales return against the customer whose balance is short. That turns a timing problem into a permanent hole in revenue, and it leaves a document someone approved. Review credit memos and write-offs for the period alongside the receivables tests.

## Receipt controls that make lapping hard to start

The controls that prevent lapping all separate the receipt of money from the record of it. If a different person logs incoming checks, if customers pay to a bank lockbox or electronic payment, and if someone outside receivables reviews the aging and handles balance disputes, a diverted check is noticed at the first customer contact.

Practical controls for a small team:

- **A mail log kept by someone outside receivables.** List every check: date, payer, amount. Compare the log total to the deposit each day.
- **Restrictive endorsement on receipt.** Stamp "for deposit only" with the company account number as soon as the mail is opened.
- **Electronic and lockbox payments.** Ask customers to pay by ACH or to a lockbox, so checks never pass through an employee's hands.
- **Statements mailed by someone else.** Monthly customer statements, sent by a person who does not post cash, invite customers to report differences to that person.
- **Review of unapplied cash and credit memos.** The owner or controller reads both lists each month.
- **Mandatory time off.** A week in which someone else posts receipts usually brings a scheme to the surface.

To start these checks on real statements and ledgers, [PreciseBankFlow](/get-started) is taking CPA and audit firms in small groups.