General ledger: how to trace a supplier payment without losing the audit trail
Trace a supplier payment from bank confirmation to bill, approval, invoice, and ledger entry so a reviewer can prove what happened and where it was recorded.
Bottom line
A useful general ledger lets a reviewer move from a payment to the payable, invoice, approval, and source document without guessing. Equal debits and credits are not enough. The record also needs the right entity, period, account, amount, and a visible correction trail.
Is it right for you?
- Start with the bank payment or provider confirmation
- Match the payment to the open bill and supplier
- Open the invoice, approval, coding, and posting record
- Confirm entity, account, period, amount, and correction history
Trace backward from cash
Pick one payment on the bank statement. The ledger entry should identify the cash account and the liability cleared. The AP subledger should identify the bill, and the bill should point to the invoice, vendor, coding, and approval.
The IRS says business records support financial statements and tax reporting [IRS, 2026]. The same links also let a manager decide whether a payment was authorized and posted in the intended period.
Keep the transaction chain intact
| Record | Question it answers |
|---|---|
| Invoice | What did the supplier charge and when? |
| Approval | Who accepted the business purpose, amount, and coding? |
| Bill or payable | When and where was the obligation recorded? |
| Payment | How, when, and from which account was it settled? |
| Ledger entry | Which accounts, entity, and period changed? |
| Correction | What changed, why, and who approved it? |
Reconcile the subledger before investigating details
Compare the total AP aging with the general-ledger accounts-payable balance. Differences can come from direct journal entries, cutoff timing, failed exports, duplicate vendors, foreign-currency treatment, or a payment applied to the wrong bill.
Name each reconciling item, its amount, owner, and expected clearing date. An unexplained difference carried month after month is not a reconciliation.
The same discipline applies to any subledger, not just AP: fixed asset registers drift from the general ledger just as often, usually from depreciation runs that post before or after a close date instead of on it.
Frequently asked questions
Are AP aging and the GL interchangeable? No. Aging lists individual supplier bills by age; the GL holds their accounting total. The two totals should agree.
Can a balanced entry be misclassified? Yes. Debits can match credits even when a posting uses an incorrect account, company, accounting period, or supplier.
Should corrections overwrite the original entry? No. Preserve the original record and create a dated, approved correction or reversal.
What is the fastest audit-trail test? Start with a bank payment and see whether a reviewer can reach the invoice and approval without using a separate spreadsheet.
What are the three main ledgers? Most businesses run a sales ledger for customer accounts and receivables, a purchase ledger for supplier accounts and payables, and the GL itself, which holds the summary control accounts that both subledgers reconcile to. This article traces the GL-to-purchase-ledger connection specifically; the same logic carries over to the sales-ledger side for customer payments.
What is an example of a GL account? Cash, accounts payable, accounts receivable, inventory, revenue, and rent expense are all examples, each with its own running debit or credit balance. Tracing one supplier bill through its invoice, sign-off, and payment steps, the way the table above lays out, shows how a single transaction touches several of these accounts at once.
That situation deserved its own writeup: Gross margin formula.