Vouching vs Tracing in Audit, With Examples

Vouching and tracing use the same documents and the same ledgers. What separates them is the direction you test in, and the direction decides which assertion you get evidence for. Pick the wrong direction and you can test a hundred items without answering the question the risk assessment asked.

The short answer

	Vouching	Tracing
Starts from	The accounting records (GL, sub-ledger, journal)	The source documents (invoices, shipping documents, receiving reports, timesheets)
Goes to	The supporting documents	The accounting records
Main assertion	Existence or occurrence	Completeness
Risk it addresses	Overstatement: something recorded that should not be	Understatement: something real that was never recorded
Typical areas	Revenue, expenses, additions to fixed assets, receivables	Liabilities, expenses accrued at year end, revenue cut-off

A simple way to remember it is vouch backward, trace forward. Vouching walks back from the number to the evidence. Tracing walks forward from the event to the number.

Vouching

When you vouch, you pick items from what the client recorded and ask: is there real support for this?

The population is the recorded balance or class of transactions. For revenue that is the sales ledger or the revenue accounts in the GL. For expenses it is the expense accounts or the AP sub-ledger.

For each selected item, look for:

• A document that supports it: an invoice, contract, receiving report or bank record. External documents are stronger evidence than ones the client created.
• The amount: does the document agree with the recorded amount? Note any difference, even small ones. A pattern of small differences is a finding.
• The date: is the transaction in the right period? Vouching gives you cut-off evidence for free if you check dates.
• The account: is it coded to the right account? An office lease booked to repairs is still an error.
• Approval, where your procedure calls for it.

Example: vouching expenses

You select 40 entries from the professional fees account. Entry 17 is $12,400 to a consulting firm dated December 12. You find the invoice: $12,400, dated December 10, for advisory work in November, approved by the CFO. That item vouches clean.

Entry 23 is $8,000 with no invoice; the client says it was an accrual and the invoice came in January. That is not an exception by itself, but now you need the January invoice, and you need to check the January entry did not book the same cost a second time.

Tracing

When you trace, you start outside the books and ask: did this make it into the records, in the right period and the right amount?

The population is the set of source documents, not the ledger. This is the step that most often goes wrong in practice. If you pick a sample from the GL and "trace" it to invoices, you have vouched. You have learned nothing about items that are missing from the GL, because a missing item can never be selected from the GL.

Example: tracing shipments to revenue

Take a sample of shipping documents from the last two weeks of the year and the first two weeks of the next. For each one, find the sales invoice and the revenue entry. You are checking that every shipment before year end was recorded as revenue in the year, and that shipments after year end were not.

Example: the search for unrecorded liabilities

The search for unrecorded liabilities is a tracing test. You look at payments made after year end and unpaid invoices received after year end, and for each one ask whether the goods or services were received before year end. If they were, the liability should be in the year-end balance. Trace those items back to the AP listing or the accruals. Anything missing is a potential understatement of liabilities and expenses.

Common mistakes

1. Sampling from the wrong population. Completeness evidence has to come from a population outside the records. If your only population is the GL, you cannot test completeness by tracing.
2. Stopping at "there is an invoice." Agreeing the vendor name is not enough. Amount, date, account and the description of what was bought all matter.
3. Calling partial matches clean. If the invoice is for $9,800 and the entry is $10,200, record the $400 difference and decide whether it is an error, not a rounding note.
4. Undocumented judgment. "Agreed to support" with a tickmark does not tell a reviewer which document, which page or which fields you checked. The reviewer has to be able to re-perform the test from your working papers.
5. Treating a three-input match as a three-way match. A three-way match is purchase order, receiving report and invoice for the same purchase. Matching three unrelated documents to an entry is not the same thing.

Where this fits in the audit

Vouching and tracing are both tests of details, a kind of substantive testing. They answer different assertions, so many audit programs use both for the same area: vouch a sample of recorded expenses for occurrence, and run the search for unrecorded liabilities for completeness.

Both tests also need to land in working papers that show exactly what was compared. Warp is built for that part. It vouches GL samples to invoices and receipts, and every result links to the page in the source document it came from, with the fields that agree and the ones that do not. Your team reviews the result instead of doing the matching. See how test of details works in Warp.