Audit fees often spike when auditors encounter disorganized records, missing documentation, or systems that don't talk to each other. Smart preparation—done months before the engagement starts—can slash costs by 20–40% and reduce the timeline from weeks to days. Here's exactly what to do.
Start with a Financial Records Audit
Before your external auditor arrives, conduct an internal review of your general ledger, bank reconciliations, and subsidiary ledgers. Look for:
- Unreconciled accounts or long-standing suspense items
- Duplicate or reversed transactions
- Entries without supporting documentation
- Transactions posted to incorrect accounts
Spending 10–20 hours now fixing obvious errors prevents auditors from billing $150–$300 per hour to hunt down the same issues. Most small to mid-market companies find 5–15 material errors this way.
Organize Your Documentation System
Auditors need access to source documents—invoices, contracts, bank statements, loan agreements, board minutes. Create a filing structure (physical or digital) grouped by audit area:
- Revenue & receivables: Sales contracts, customer agreements, invoicing records
- Purchases & payables: Purchase orders, vendor invoices, payment records
- Payroll & benefits: Payroll registers, tax filings, employee files
- Fixed assets: Purchase documentation, depreciation schedules, disposal records
- Debt & equity: Loan documents, interest calculations, share certificates
Upload everything to a shared folder (Google Drive, Dropbox, or a secure auditor portal) at least two weeks before the fieldwork begins. This cuts auditor search time from hours to minutes.
Reconcile Your Balance Sheet Accounts
This is the single highest-impact prep task. Auditors will test every balance sheet line item, so get ahead:
- Bank accounts: Reconcile monthly statements. Resolve any reconciling items older than 30 days.
- Accounts receivable: Age your customer balances. Identify uncollectible accounts and create a realistic allowance estimate.
- Inventory: If you hold stock, complete a physical count and reconcile to your general ledger. Document any write-offs or obsolescence.
- Fixed assets: List all assets with cost, accumulated depreciation, and disposal dates. Verify depreciation methods are consistent.
- Accounts payable: Match unpaid invoices to your general ledger. Flag any outstanding vendor statements that don't match.
Companies that complete this prep work typically see audit fees drop $5,000–$15,000 compared to those that don't.
Prepare a Detailed Trial Balance
Provide your auditor with a trial balance that ties to your financial statements, dated as close to your fiscal year-end as possible. Include account numbers, descriptions, and balances. Flag unusual or large transactions—don't make auditors dig for explanations.
Address Prior-Year Audit Issues Early
If your last audit flagged control weaknesses, misstatements, or unresolved questions, fix them now. Document what you've done. Auditors spend less time retesting when they see corrective action.
Communicate Changes Upfront
Send your auditor a memo (before fieldwork starts) covering:
- New accounting systems implemented
- Significant transactions or business changes
- Related-party dealings
- New loans, leases, or contracts
- Changes in accounting policies
This prevents auditors from discovering surprises in the data and asking for extra testing.
Set Up Auditor Access Early
Agree on logistics at least three weeks before the audit starts:
- Will auditors work on-site, remotely, or hybrid?
- Do they need VPN access to your systems?
- Who owns the general ledger system, and can auditors access prior-year data?
- Which team member will be the primary contact?
Delays here add days to the timeline and inflate fees.
Engage the Right Firm
If you're hiring for the first time, use a service like Mercoly to compare audit firms in your region, see their experience with your industry, and read client feedback. Firms specializing in your sector often charge 15–30% less because they work faster and know your compliance landscape.
Frequently Asked Questions
Q: How much should I expect to pay for an external audit? A: Small businesses typically pay $3,000–$8,000; mid-market firms $10,000–$50,000; larger entities $50,000+. Preparation can save 20–40% across any size.
Q: What happens if my accounting system doesn't integrate with the auditor's software? A: You'll need to export data manually and reconcile it, which adds 5–15 hours to the audit timeline and $750–$4,500 in fees. Discuss system compatibility before engagement.
Q: Should I hire a bookkeeper to clean up my records before the audit? A: If you have more than three months of backlog or unreconciled accounts, yes—a bookkeeper at $25–$50/hour costs less than an auditor discovering the same problems at $150–$300/hour.
Start your audit prep today—reach out to trusted providers on Mercoly to get firm recommendations and timelines.