Cash and loan balances depend heavily on independent bank letters. The evidence problem is rarely conceptual; it is calendaring and follow-up.
Start from the account list, not the inbox
List every account and facility on the trial balance, including dormant accounts and guarantees. Missing a small foreign-currency account often surfaces late in review.
Allow real lead time
For local banks, two to three weeks is a common working assumption; groups with overseas branches need more. Sending requests the week before fieldwork is a recovery tactic, not a plan.
Track exceptions, not just arrivals
A confirmation that disagrees with the ledger is more valuable — and more urgent — than a perfect match. File the investigation memo beside the letter.
When the letter does not arrive
Document chase history and switch to agreed alternative procedures with the auditor: subsequent statements, reconciliations, and testing of reconciling items. Silence without a paper trail looks like neglect.