IRS Audits for Self-Employed and Small Business Owners

How a self-employed audit usually runs

A Schedule C audit can be done by mail, at an IRS office or at your place of business; the IRS audit page says field audits may take place at your home, business or your representative’s office. In a mail audit, the letter lists the items under review. Office and field exams of a business return include required checks of income, described below. Our guide to the types of IRS audits explains how to tell which you have.

Not every IRS letter about business income is an audit. If the IRS received a Form 1099 that does not match your return, you may get a CP2000 instead, which is an automated income-matching notice. For general background, see what happens during an IRS audit.

One point surprises many owners: a change to Schedule C profit also changes self-employment tax. The IRS figures self-employment tax on Schedule SE from net earnings from self-employment, so every dollar of disallowed expense or added income can raise both income tax and self-employment tax. Examiners also have published Audit Techniques Guides for many industries; the IRS says they “help IRS examiners during audits” and are “also useful to small business owners,” so the one for your industry is worth reading before the first meeting.

Income: the probes every business return gets

The Internal Revenue Manual section on examining income (IRM 4.10.4, revised August 29, 2025) tells examiners what they must do on a Schedule C return before accepting reported income. These minimum income probes include:

• An interview about your business history, how you keep records, cash on hand, and “possible nontaxable sources of funds, gifts, loans.” Examiners also ask about bartering.
• A financial status analysis, which compares the income you reported with what you appear to spend, to spot a cash-flow gap.
• A tour of the business site, generally required in field exams and optional in office audits.
• A review of internal controls to judge how reliable your books are.
• Reconciliation of income: your books to your return, and your return to the information returns (Forms 1099 and similar) the IRS received.
• Testing gross receipts against source documents “to verify that all the gross receipts are accounted for.”
• A bank account analysis of business and personal accounts, including investment accounts.
• Business ratio analysis and a mandatory check of e-commerce and internet activity.

If the books are missing or unreliable, or the analysis shows a material gap, examiners can use formal indirect methods to estimate income: the bank deposits and cash expenditures method, source and application of funds, markup, unit and volume, and net worth. By law (IRC 7602(e), quoted in IRM 4.10.4) the IRS “shall not use financial status or economic reality examination techniques” unless it has a reasonable indication that there is unreported income. That limit applies to the formal methods, not to the routine probes above.

Expenses: ordinary, necessary and proven

IRC 162(a) allows a deduction for “all the ordinary and necessary expenses paid or incurred during the taxable year” in carrying on a trade or business. In an audit, that becomes three questions for each expense: did you pay it in that year, was it for the business rather than personal, and is it the kind of cost a business like yours has?

The IRS’s recordkeeping page lists the documents that answer them: for expenses, “canceled checks or other proof of payment, cash register tape receipts, account statements, credit card receipts and statements, and invoices,” and it notes that “a combination of supporting documents may be needed.” Publication 583 adds that proof of payment alone “does not establish you are entitled to a tax deduction.” A card statement line that says “Home improvement store, $640” proves payment; the invoice showing shelving for your workshop shows the purpose.

Common trouble spots in small business exams:

• Mixed accounts. Paying personal and business costs from one account forces you to explain every line. A separate business account is the simplest fix for future years.
• Personal costs on Schedule C. Family phones, groceries, clothing you can wear outside work and commuting are frequent adjustments.
• Large equipment purchases. Keep records of when you bought an asset, its cost, how you used it and any depreciation or section 179 deduction, as the IRS recordkeeping page lists.
• Cost of goods sold and inventory. Supplier invoices and inventory counts support it; examiners test it against gross receipts.

If receipts are missing, our guide to audits with missing records explains what can replace them. For deductions owners often miss when filing, see 12 tax deductions small business owners miss.

Car, travel and meals: the stricter proof rules

IRC 274(d) blocks deductions for travel away from home, gifts and listed property such as a car used partly for business unless you prove, with adequate records or evidence that corroborates your own statement, the amount, time and place, business purpose and business relationship. Publication 463 (2025) turns that into a record list:

• Mileage logs. Record trips “at or near the time”; Publication 463 says a weekly log counts as timely. A record kept for part of the year can prove business use for the whole year if you show the period was representative.
• Receipts. Generally required for lodging and for other expenses of $75 or more.
• Meals. The deduction for business food and beverages generally cannot exceed 50 percent of the cost (IRC 274(n)(1)). Publication 463 says a restaurant receipt should show the restaurant’s name and location, the number of people served, and the date and amount.
• No estimates. Publication 463 says you “can’t deduct amounts that you approximate or estimate,” and the courts’ Cohan estimating rule does not apply to these items.

Home office: regular and exclusive use

The IRS says you must “regularly use part of your home exclusively for conducting business” and show that it is your principal place of business. A separate free-standing structure, such as a studio or garage, can qualify if it is used regularly and only for the business. A spare room that doubles as a guest room or family den usually fails the exclusive-use test. Publication 587 covers special rules for daycare providers and for storing inventory or product samples.

There are two ways to figure the deduction:

• Simplified option: $5 per square foot of the business part of the home, up to 300 square feet, with no depreciation (IRS, page reviewed March 2, 2026). Prove the square footage and the use, for example with a floor plan and photos.
• Regular method: the business percentage of actual costs such as mortgage interest or rent, insurance, utilities, repairs and depreciation, figured on Form 8829. Keep the bills and the measurements behind the percentage.

The deduction is for the self-employed. The IRS notes that employees can no longer claim a home office deduction, so a W-2 job worked from home does not qualify even if you also have side income; only the space used for your own business can.

Hobby or business: when losses keep repeating

A Schedule C that shows a loss year after year, especially alongside wage income, can lead an examiner to ask whether the activity is “engaged in for profit” under IRC 183. If it is not, the IRS fact sheet on hobbies (FS-2022-38) says you “can’t use a loss from the activity to offset other income,” and the income is still reported, on Schedule 1.

Treasury Regulation 1.183-2(b) lists nine factors, and says “no one factor is determinative”:

1. How you carry on the activity (businesslike records, changing methods to improve profit)
2. Your expertise or your advisors’
3. The time and effort you put in
4. Whether assets used in the activity may appreciate
5. Your success in other activities
6. Your history of income or losses in this activity
7. The amount of any occasional profits
8. Your financial status
9. Elements of personal pleasure or recreation

IRC 183(d) creates a presumption of profit motive if the activity shows a profit in 3 or more of 5 consecutive years (2 of 7 for horse breeding, training, showing or racing). The IRS can rebut it. Evidence that helps: a business plan, a separate account, marketing, records of changes you made to cut losses, and time logs.

Workers, 1099s and payroll: when the audit widens

If you pay people, an income tax audit can raise employment questions. Whether a worker is an employee or an independent contractor depends on “the extent of the right to direct and control the worker,” looking at behavioral control, financial control and the type of relationship, according to the IRS. If status is unclear, the business or the worker can file Form SS-8 for an IRS determination. This page does not cover worker classification in depth; get advice before changing how you treat workers mid-audit.

Keep employment tax records for at least 4 years after the tax is due or paid, whichever is later. If payroll taxes you withheld were not paid over, the issue becomes collection of the trust fund taxes and possibly personal liability; see the trust fund recovery penalty guide and payroll tax problem help. For owners already facing a balance, our page for small business owners covers the options.

Records checklist before the first appointment

Gather records only for the year and items the letter names, but expect income to be in scope in any office or field exam. Send copies, never originals, and organize them “by year and type of income or expense” with a summary, as the IRS asks.

• The return under audit and the letter, with every item marked
• Your IRS wage and income transcript for that year (shows the Forms 1099 the IRS received)
• All business and personal bank, card and investment statements for the year
• Sales records: invoices, receipt books, register tapes, payment-platform and merchant reports
• Proof for non-income deposits: loan papers, gift letters, transfer records
• Expense support: invoices plus proof of payment, grouped by Schedule C line
• Mileage log, calendar and trip records; lodging receipts and other receipts of $75 or more
• Home office measurements, photos and, for the regular method, the home’s bills
• Asset purchase records and depreciation schedules
• Payroll records, Forms W-2 and 1099 you issued, and contractor agreements
• Your books (software file or ledger) and a reconciliation of the books to the return

Handling it yourself, free help, and when a representative helps

A mail audit about one or two well-documented expenses is often something you can answer yourself. Representation is more useful when the IRS is doing an office or field exam of the whole business, when it is using bank deposits or another indirect method to estimate income, when records are thin, when more than one year is involved, or when there is any suggestion of fraud, which calls for a tax attorney specifically. A representative under Form 2848 can deal with the examiner for you; see when audit representation is worth it.

• Taxpayer Advocate Service: free help if an IRS problem causes hardship or normal channels have failed, 877-777-4778 (IRS.gov, 2026).
• Low Income Taxpayer Clinics: LITCs represent eligible taxpayers in audits for free or a small fee.

If the audit ends with tax due, interest runs at the federal short-term rate plus 3 percentage points, reset quarterly (7% (IRS.gov, Jul-Dec 2026) this quarter); see the 30-day letter for your choices and what to do if you can’t pay.

Global Gate Tax Relief’s team includes licensed tax attorneys, enrolled agents and CPAs. It offers a free consultation and, if it takes the case, quotes a flat fee upfront; it does not promise outcomes. Request a free case review or call 1-877-800-8180.

Frequently asked questions

Keep reading in the IRS Audit Guide

• Audit with missing recordsWhat can replace receipts, and what never to do.
• Types of IRS auditsMail, office and field audits compared.
• The 30-day letterYour choices after the examiner's report.
• Small business owners who owe the IRSOptions when the business already has a balance.
• Trust fund recovery penaltyWhen unpaid payroll taxes become personal.