Walking into an IRS audit without receipts does not automatically wipe out your deductions, but it does put the work on you to prove each expense some other way. What happens if you don’t have receipts for an IRS audit depends on the type of expense, the dollar amount, and how much secondary evidence you can produce. Small purchases usually never needed a receipt in the first place. Most other expenses can be salvaged through bank records, vendor copies, or a reasonable estimate under a decades-old court rule. A narrow but important set of categories, including travel and vehicle use, follow stricter rules where nothing but proper contemporaneous records will do.
Whether You Needed a Receipt at All
Check the dollar amount before you assume the worst. IRS regulations generally require documentary evidence only for expenses of $75 or more. Lodging while traveling away from home is the exception and always needs a receipt no matter how small the charge.1Internal Revenue Service. Revenue Ruling 2003-106 For anything below $75, a credit card statement or bank record showing the vendor, date, and amount is enough.
The threshold works transaction by transaction. Ten $50 purchases don’t cross the line just because they total $500. Each one stands on its own. You still need some record of what the expense was for, though. The IRS will not accept a bare claim that money was spent.
The Cohan Rule: Estimates When Receipts Are Gone
For larger expenses where the original receipt is lost, the main legal protection comes from a 1930 appellate decision, Cohan v. Commissioner. The entertainer George M. Cohan could not produce exact receipts for business travel but convinced the court the spending was real. The court held that once a taxpayer establishes an expense actually happened, the IRS cannot zero it out entirely; it must allow a reasonable estimate.2Cornell Law School. Cohan Rule
The catch is that estimates resolve doubts against the taxpayer. If you claimed $5,000 in supplies and the auditor accepts that you spent something without being able to pin down the figure, the allowed number will land below what you originally deducted. You also need some factual basis for the estimate, such as testimony about your normal purchasing patterns, industry benchmarks, or partial records covering part of the year. The rule is a safety net, not full recovery.
Where the Cohan Rule Does Not Apply
Congress carved out categories that require strict documentation with no room for estimation. Under Section 274(d), the Cohan rule cannot be used for travel expenses (including meals and lodging away from home), business gifts, or listed property such as vehicles used for business.3Office of the Law Revision Counsel. 26 USC 274 – Disallowance of Certain Entertainment, Etc., Expenses IRS regulations confirm that Section 274(d)’s strict substantiation rules supersede the Cohan approach for these categories.4eCFR. 26 CFR 1.274-5T – Substantiation Requirements (Temporary)
For those expenses, you need records showing four elements: the amount, the time and place (or date and description for gifts), the business purpose, and the business relationship to anyone who received a benefit. Without records covering all four, the deduction is gone. A missing mileage log is the classic example where after-the-fact estimation will not save you.
Listed property under Section 280F includes passenger vehicles, other transportation property, and property used for entertainment or recreation.5Office of the Law Revision Counsel. 26 USC 280F – Limitation on Depreciation for Luxury Automobiles Computers came off the listed-property list after the 2017 tax law changes, so computer expenses can be estimated under Cohan if other documentation exists. Also worth knowing: entertainment expenses are not deductible at all for tax years after 2017, no matter how well documented.6Office of the Law Revision Counsel. 26 U.S. Code 274 – Disallowance of Certain Entertainment, Etc., Expenses
Alternative Evidence the IRS Will Accept
When the original receipts are gone, your job is to build a paper trail from other sources. The IRS accepts a combination of supporting documents, and receipts specifically are not required if other records establish the payee, the amount, the date, and the business nature of the purchase.7Internal Revenue Service. What Kind of Records Should I Keep
The strongest secondary evidence tends to be:
- Bank and credit card statements showing the vendor name, transaction date, and amount.
- Canceled checks, which the IRS recognizes alongside electronic funds transfer records as valid payment documentation.7Internal Revenue Service. What Kind of Records Should I Keep
- Electronic payment histories from services like PayPal, Venmo, or Zelle.
- Calendars and appointment books that connect a financial transaction to a specific business activity. A $200 restaurant charge paired with a calendar entry for a client meeting that day is more persuasive than either record alone.
- Mileage logs and contemporaneous notes. Anything written at or near the time of the expense carries far more weight than a reconstruction made months later.
Financial statements alone show that money moved, not what it was for. A $300 charge at an office supply store could be business supplies or your child’s school supplies. Something has to connect the payment to a business purpose, which is where calendars, notes, and the context of your operations come in.
Rebuilding Your Records Before the Auditor Pushes Back
If you know records are missing, start reconstruction as soon as you get the audit notice rather than waiting to be asked twice.
Third-Party Sources
Vendors are often the best resource. Most businesses keep transaction records and can produce duplicate invoices or account histories. Banks retain account records for at least five years under federal requirements, and many keep them longer; retrieval fees vary by institution. Employers may have copies of expense reports or reimbursement records you submitted. Landlords, utility companies, and insurers can all furnish statements showing what you paid and when.
The IRS itself has authority under IRC 7602 to issue summonses to third parties like banks for financial records.8Internal Revenue Service. Summonses on Third-Party Witnesses Gathering these documents yourself first shows good faith and lets you frame each expense on your own terms.
Records Destroyed by Disaster
If records were destroyed in a federally declared disaster, Publication 584 walks through documenting losses using schedules that feed into Form 4684.9Internal Revenue Service. Publication 584, Casualty, Disaster, and Theft Loss Workbook Auditors generally give more latitude when records disappeared through no fault of the taxpayer, and a disaster declaration is objective proof of that.
Written Statements as a Last Resort
When no third-party documentation exists at all, a detailed written statement can serve as final evidence. It should describe what was purchased, why it was necessary for the business, the approximate amount, and why the original documentation is unavailable. These statements carry weight only when the details line up with other verified facts about the business. A sworn claim of $10,000 in travel expenses from a business that runs entirely online will invite skepticism.
Presenting What You Have
Organize alternative evidence for the auditor rather than dumping it. A summary sheet listing each disputed expense with the date, amount, vendor, and the specific secondary source supporting it makes the auditor’s job easier and improves your odds. Link each line to its corresponding document.
What Lost Deductions Actually Cost
Losing deductions is only the first cost. When the IRS disallows expenses and determines you owe more tax, interest and penalties stack on top.
Interest on Underpayments
Interest on unpaid tax compounds daily and runs from the original due date of the return until paid in full. The rate is the federal short-term rate plus three percentage points, updated quarterly. For the second quarter of 2026, the underpayment rate is 6%.10Internal Revenue Service. Internal Revenue Bulletin 2026-08 On a $10,000 underpayment, that’s roughly $600 a year in interest alone, and daily compounding pushes the real cost higher over time.
The 20% Accuracy-Related Penalty
If the IRS determines the underpayment resulted from negligence or disregard of tax rules, it can impose a penalty of 20% of the underpayment.11Office of the Law Revision Counsel. 26 U.S. Code 6662 – Imposition of Accuracy-Related Penalty on Underpayments Negligence includes any failure to make a reasonable attempt to comply with the tax code. Claiming deductions you cannot support with any evidence is a textbook trigger. The 20% applies to the portion of the underpayment attributable to the negligence, not necessarily the entire balance.
Civil Fraud Is a Higher Bar
In rare cases the IRS asserts a civil fraud penalty of 75% of the underpayment.12Office of the Law Revision Counsel. 26 U.S. Code 6663 – Imposition of Fraud Penalty This takes clear and convincing evidence that you intentionally evaded taxes, not just sloppy records. Inadequate records are one “badge of fraud” the IRS looks for, but missing receipts alone won’t get there. Fraud requires an affirmative act of deception, like fabricating expenses or hiding income.13Internal Revenue Service. Civil Fraud
Reasonable Cause
You can avoid the 20% accuracy-related penalty by demonstrating reasonable cause and good faith. The IRS weighs the specific circumstances, including the nature of the error, your compliance history, and whether you tried to determine the correct tax.14Internal Revenue Service. Reasonable Cause and Good Faith Records destroyed in a flood, a fire at your accountant’s office, or a similar event beyond your control support this argument. Having no explanation at all for why records are missing makes the defense much harder to sustain.
Appeal Rights If Deductions Are Disallowed
If the auditor disallows deductions and you disagree with the proposed changes, you do not have to accept the result. The IRS has a formal appeals process that operates independently from the examination division.
Requesting an Appeal
You generally have 30 days from the date of the IRS letter to file a protest. For disputes of $25,000 or less per tax period, the simplified process uses Form 12203 (Request for Appeals Review). Larger amounts require a formal written protest identifying each disputed item, explaining your position, and including supporting facts and law. Send the protest to the IRS address on the letter explaining your appeal rights, not to the Appeals office directly.15Internal Revenue Service. Preparing a Request for Appeals
Tax Court
If appeals do not resolve the dispute, the IRS will issue a statutory notice of deficiency, sometimes called the 90-day letter. You have exactly 90 days from the date of that notice to file a petition with the U.S. Tax Court. The court cannot extend this deadline for any reason, and a late petition means dismissal.16United States Tax Court. Guidance for Petitioners: Starting a Case If you miss the 90-day window, your only option is to pay the tax and then sue for a refund in federal district court or the Court of Federal Claims.
Audit Reconsideration If Documents Turn Up Later
If you find supporting documents after the audit closes, you can request audit reconsideration. Submit a written request with the new documentation, a copy of Form 4549 if you have it, and an explanation of which items you are disputing.17Taxpayer Advocate Service. Audit Reconsiderations The IRS may reduce the assessed tax in full or in part, or find that the new evidence does not change the outcome.