Overview

An IRS field audit is the most in-depth type of examination. Unlike correspondence audits (handled by mail) or office audits (at an IRS office), a field audit involves an agent visiting your premises or your representative’s office to review original documents and ask detailed questions. Field audits are chosen when the IRS needs to see business operations or a larger volume of records in person (IRS, Understanding Audits).

Typical timeline (what to expect)

  • Notice and response window: You’ll receive a written audit notice that explains the scope; respond within the stated time (commonly 30 days). Some notices proposing adjustments are called a “30‑day letter” (IRS Pub. 556).
  • Scheduling the visit: After notice, the agent will propose dates. Expect coordination to take days to weeks.
  • On-site review: Most field visits last a few hours to several days depending on the size of the business and the volume of documents. Complex cases can require multiple visits.
  • Field work completion: The agent will often take notes and copies; field work may close in weeks to months.
  • Report and resolution: You may receive a proposed changes report and have time to respond or appeal; many matters are resolved within 30–120 days after the field visit, but timelines vary.

Documentation checklist — organize before the agent arrives

Arrange records chronologically and put a simple index or tabbed binder on top. See our related guide on building an audit binder: “Preparing an Audit Binder: Documents to Organize Before an IRS Audit” (https://finhelp.io/glossary/preparing-an-audit-binder-documents-to-organize-before-an-irs-audit/).

Essential documents to have ready:

  • Identification and legal documents
  • Photo ID for the taxpayer and representative (if present)
  • Business formation documents (articles of organization, partnership agreement)
  • Income
  • All W-2s, 1099s, K-1s for the relevant years
  • Bank deposit records and cash receipts
  • Expenses and deductions
  • Receipts and invoices for expenses claimed
  • Canceled checks, credit card statements, and merchant reports
  • Payroll records, 940/941 filings, and payroll registers
  • Business records
  • General ledger, journal entries, profit & loss and balance sheets
  • Contracts, leases, invoices, and appointment logs
  • Mileage logs and vehicle use substantiation (if applicable)
  • Asset and property
  • Deeds, mortgage statements, settlement statements
  • Depreciation schedules and asset purchase invoices
  • Prior tax returns and correspondence
  • Copies of prior-year returns and audit responses
  • Any IRS notices for the same tax years

Record retention note: Keep records for at least three years, but understand exceptions — the IRS can go back six years if you understate gross income by more than 25%, and there is no limit for fraud. See IRS guidance on how long to keep records (https://www.irs.gov/businesses/small-businesses-self-employed/how-long-should-i-keep-records).

What happens during the on-site visit

  • Professional demeanor: The agent will explain their scope, review records, and ask clarifying questions. You or your representative should stay factual and concise.
  • Document handling: Expect the agent to request copies. Keep originals unless the agent must take them as exhibits; always ask for a receipt.
  • Interviews: The agent may interview owners or employees. Advise staff to be cooperative but to refer technical tax questions to the primary contact or tax advisor.

After the visit — follow-up, proposed changes, and appeals

  • Proposed adjustments: If the agent proposes changes, you usually receive a written report explaining proposed adjustments, additional tax, and any penalties.
  • Responding: You’ll have time to submit additional documents, explanations, or corrections. Use this window to organize an appeal if needed.
  • Appeals: If you disagree, you can request conference with the IRS Appeals Office or pursue administrative remedies; for litigation, tax court is an option. See our guide on concise audit responses for templates and timelines: “Preparing a Concise Audit Response: Documents, Timelines, and Best Practices” (https://finhelp.io/glossary/preparing-a-concise-audit-response-documents-timelines-and-best-practices/).

Top practical tips from practice

  • Hire representation early: A CPA, EA, or tax attorney familiar with field audits can manage documents and communications. In my practice, early representation often shortens on-site time and reduces follow-ups.
  • Build an audit binder: Organize and index documents before the visit — it signals cooperation and speeds review (see audit binder link above).
  • Don’t sign anything you don’t understand: Refuse to sign agreements or waivers without review by your advisor.
  • Be selective with originals: Provide copies where possible; only provide originals when required and get a receipt.
  • Track communications: Keep a log of names, dates, and topics discussed during the audit.

Common mistakes and how to avoid them

  • Handing disorganized records: This forces the agent to dig deeper and can lengthen the audit.
  • Ignoring notices: Nonresponse can lead to default assessments and penalties.
  • Admitting fault: Be factual, but avoid speculative or self-incriminating statements.

Taxpayer rights and resources

You have rights during an audit, including the right to representation, to professional and courteous treatment, and to appeal proposed changes (see “Taxpayer Rights During an Audit” for details: https://finhelp.io/glossary/taxpayer-rights-during-an-audit-what-the-irs-must-provide/). The IRS publishes an examiner’s process and appeals rights in Publication 556 (https://www.irs.gov/pub/irs-pdf/p556.pdf) and outlines the Taxpayer Bill of Rights (https://www.irs.gov/taxpayer-bill-of-rights).

When you don’t have requested documentation

If you cannot produce documents, the IRS may reconstruct income using available data (bank records, 1099s) and make an estimated assessment. If records are missing, provide plausible corroborating evidence and an explanation — but expect heavier scrutiny.

Final note and disclaimer

Field audits are often detailed but resolvable with organized records and an informed response. This article is educational and not a substitute for personalized tax advice. For help with a current audit, consult a qualified tax professional or an enrolled agent who can represent you before the IRS.

Authoritative sources

Internal resources

Professional disclaimer: This content is educational and reflects industry-standard practices as of 2025; it does not replace personalized tax advice.