Understanding the Types of Audits

Before preparing, it's important to know what kind of audit you're facing. The three most common types for businesses are:

  • IRS Tax Audit: A review of your tax return to verify income, deductions, and credits. Can be conducted by mail, at an IRS office, or on-site (field audit).
  • External Financial Audit: An independent review of your financial statements by a CPA firm, typically required by investors, lenders, or regulations.
  • Internal Audit: A self-initiated review of internal controls, processes, and financial accuracy — a proactive practice to catch issues before they become problems.

This guide focuses primarily on external and tax audits, as these are the most stressful for business owners.

Step 1: Understand the Scope

Read the audit notice carefully. What years are under review? What specific items are being examined — income, deductions, payroll taxes? Understanding the exact scope lets you focus your preparation efficiently rather than pulling every document you own.

Step 2: Organize Your Financial Records

Auditors work most efficiently — and form more favorable impressions — when records are well organized. Gather and organize:

  • Bank statements for all business accounts
  • Invoices and receipts (income and expenses)
  • Payroll records and tax filings (Forms 941, W-2, 1099)
  • General ledger and trial balance
  • Prior-year tax returns
  • Loan documents and contracts
  • Fixed asset schedules and depreciation records

Step 3: Reconcile Your Accounts

Before handing anything over, make sure your bank statements reconcile to your books, and your books reconcile to your tax return. Discrepancies that you can't explain are the fastest way to extend an audit's scope.

Step 4: Review What's Being Questioned

If the audit targets specific deductions — like meals, travel, or home office — compile the documentation for those items specifically. For each questioned expense, you should be able to show:

  1. The amount and date
  2. The vendor or payee
  3. The business purpose
  4. The receipt or invoice

Step 5: Engage a Professional

For anything beyond a simple correspondence audit, engaging a CPA, tax attorney, or enrolled agent is strongly advisable. They can:

  • Communicate directly with auditors on your behalf
  • Identify potential issues before the auditor does
  • Help you respond accurately without volunteering unnecessary information
  • Negotiate settlements if adjustments are proposed

Step 6: Know Your Rights

Taxpayers have rights during an audit, including the right to professional representation, the right to appeal audit findings, and the right to know why information is being requested. The IRS Taxpayer Bill of Rights is a useful reference.

After the Audit: Prevent Future Issues

Use an audit as a catalyst to strengthen your bookkeeping systems. Common improvements include:

  • Switching to dedicated accounting software
  • Implementing a document retention policy
  • Scheduling quarterly financial reviews
  • Separating personal and business finances completely

The best audit preparation is simply maintaining clean, accurate records year-round.