An IRS audit checklist starts with the letter. List each tax year and return item the IRS questions, then write beside each item the records that support it, who holds them, the date you asked and the status. The checklist is finished when every examined item has its records in the file before the response date.
What does the IRS audit letter tell you to gather?
An IRS audit letter is the written notice that a return was selected for examination. It names the tax year, the items under review, how the audit will be held and the date a response is due. Read it line by line before asking the client for anything, because the letter sets the scope of the checklist.
The IRS says on its IRS audits page (last reviewed 17 February 2026) that it notifies a taxpayer of an audit by mail and does not start one by phone. The same page says an audit happens either by mail or through an in-person interview, which can be at an IRS office, the taxpayer's home or business, or the accountant's office. For a mail audit, the letter "will request additional information about certain items shown on the tax return." The IRS also says the letter carries all contact information and instructions.
Four things on the letter decide what goes on the list:
- The tax year or years. The IRS audits page says the IRS can generally include returns filed within the last three years and usually does not go back more than six. A letter that names two years means two sets of records.
- The items questioned. A mail audit letter usually names specific lines, such as charitable contributions, car expenses or a Schedule C category. Each named item becomes its own row.
- The format. A mail audit asks for copies sent as the letter instructs. An in-person audit asks the client, or the client's representative, to bring records to a meeting.
- The response date. This is the date the checklist works back from.
IRS Publication 556 (revised September 2013), which covers examinations, appeals and claims for refund, says plainly: "The IRS will tell you which records you will need." That line is the best rule for scope. Gather what the letter names. A checklist that tries to rebuild the whole return wastes the client's time and can widen a conversation that the letter kept narrow.
Write down anything the letter does not make clear, such as whether it covers a spouse's Schedule C or only the joint return's itemized deductions. Ask the examiner rather than guessing.
Building the IRS audit checklist one examined item at a time
An IRS audit checklist built item by item has one row for each return line the letter questions. Each row names the records that prove the amount on that line, who holds each record, when you asked for it and whether it has arrived. A line with no supporting record yet stays open until one is in the file.
Start from the return itself. For each questioned line, find the figure that was filed and ask what would prove it. A wage figure is proved by a W-2. A business expense is proved by receipts, invoices and proof of payment. A deduction for mortgage interest is proved by the lender's year-end statement. The firm's own workpapers show where each number came from, which tells you which documents to pull first. The post on tying source documents to the tax return covers that tie-out during review; at audit time the same trail runs backward, from the line to the paper.
The IRS lists the kinds of records an examiner may ask for on its page IRS audits: records we might request (last reviewed 17 January 2026). It names receipts, bills, canceled checks, legal papers, loan agreements, logs or diaries, tickets, medical and dental records, theft or loss records, employment documents and Schedule K-1s. It also asks that receipts be presented by date with notes on what each was for, and that travel tickets be labelled with the business purpose of the trip.
An example IRS audit checklist
Here is a filled-in example for a fictional client, Dana Reyes, whose 2024 return was selected for a mail audit of three items. Every name, amount and date is an example.
| Examined item (2024 return) | Records that support it | Who holds them | Date requested | Status |
|---|---|---|---|---|
| Schedule C car and truck expenses, $6,410 | Mileage log for 2024; fuel and repair receipts | Client | Oct 2 | Log received, receipts missing |
| Schedule C supplies, $3,280 | Vendor invoices; card statements ending XXXX-4821 | Client; card issuer | Oct 2 | Received |
| Schedule A charitable gifts, $4,500 | Receipts or letters from each charity; canceled checks | Client; charities | Oct 2 | Two of three received |
| Supporting workpapers | Firm's 2024 workpaper file and organizer | Firm | Oct 1 | In file |
The "who holds them" column matters most. A row the client can fill tonight is a different job from one that needs a letter to a charity or a bank. Rows that depend on a third party should be requested first.
Keep one row per examined item even when the records overlap. A card statement may support both supplies and car expenses. List it on both rows, so ticking one off does not hide a gap in the other.
Records an IRS audit asks for that the tax file never held
Many records an IRS audit asks for were never sent to the firm. The tax file usually holds forms and summaries, such as W-2s, 1099s and the client's own totals. An examiner wants the evidence behind those totals: bank statements, mileage logs, receipts, bills and basis records the client kept at home or never kept at all.
The gap is normal. A client with a sole proprietorship might have sent the firm a one-page summary of expenses by category. The return was prepared from that summary. When the IRS questions the supplies line, the summary is not enough; the invoices and proof of payment behind it are what count. The IRS page What kind of records should I keep (last reviewed 3 August 2026) lists supporting documents for expenses as canceled checks or other proof of payment, cash register tape receipts, account statements, and credit card receipts and statements.
Common records the firm never received:
- Bank and card statements for the months behind a questioned expense or a deposit total.
- Mileage logs. The IRS records-request page says logs or diaries may show travel dates, locations, business purpose and mileage.
- Receipts and vendor invoices for each expense category on the letter.
- Basis records for property sold. The IRS records page lists purchase and sales invoices, real estate closing statements and proof of payment as asset records, which show the purchase price and the cost of improvements.
- Loan agreements when interest was deducted. The records-request page asks for the original loan, a year-end interest statement and a breakdown of how the money was used.
- Legal papers behind a settlement or property purchase.
Two client types bring special records. A client with digital assets may need exchange histories and wallet records that no form summarized; the cryptocurrency tax document checklist lists them. A client living abroad may need foreign payslips, account statements and travel records; the expat tax document checklist covers those.
When records arrive, they tend to arrive as a mix of phone photos, PDFs and forwarded emails. Schema CPA sorts each page by document type, issuer and period and flags a statement month that is missing from a run, which helps a firm see whether, say, all twelve card statements are actually in. The workflow overview shows those steps.
How should preparing for an IRS audit start before the deadline?
Preparing for an IRS audit should start the day the letter arrives. First confirm the firm is authorized to speak for the client, then request third-party records, then gather what the client holds, and ask for more time early if records will not arrive before the response date. Order matters because third parties are the slowest.
Authorization. IRS Publication 556 says a taxpayer can be represented by a federally authorized practitioner, such as an attorney, CPA, enrolled agent, enrolled actuary or the preparer who signed the return, and that representation in the taxpayer's absence needs proper written authorization, such as Form 2848. It adds that the "third party designee" box on a return does not replace Form 2848. What Form 2848 and Form 8821 each allow, and when to collect them, is covered under authorizations to include in client onboarding.
Third-party records next. Charities, banks, lenders and former employers can take weeks. Send those requests in the first days, and log the date sent in the checklist's date-requested column.
Client records after that. Send the client a short list built from the checklist rows they own, not a general request for "everything from 2024." Name the document, the period and the item it supports.
More time. The IRS audits page says the IRS "can ordinarily grant you a one-time automatic 30-day extension." For a mail audit, the request goes in writing by fax or mail to the address on the letter. For an in-person audit, the request goes to the assigned auditor, or the auditor's manager if needed. If a checklist row depends on a slow third party, ask for that extension well before the response date rather than on it.
Client preparation. Walk the client through what the letter asks and what the checklist shows, so the client is not surprised by any question. Explain who will talk to the examiner. Publication 556 says that if a taxpayer wants to consult a representative during an interview, the IRS in most cases must suspend and reschedule the interview.
After the response is sent, keep the checklist with the file. The post on how long to keep client tax documents and copies of returns covers retention periods, and that schedule applies to audit files as well.
When IRS audit records are lost or must be rebuilt
IRS audit records are sometimes gone: thrown out, lost in a move or destroyed in a disaster. Lost records can often be rebuilt from copies held by others, such as banks, card issuers, title companies, contractors and the IRS itself. A rebuilt record should be labelled as a copy or reconstruction on the checklist, with its source.
The IRS page on reconstructing records after a natural disaster or casualty loss (last reviewed 29 July 2026) lists places to look:
- Tax returns. Return transcripts through the Get Transcript tool, by phone, or by mail with Form 4506-T. Copies of past returns can be requested with Form 4506.
- Bank and card records. For items bought by card, the page says to contact the credit card company or bank for past statements. Its business records section also suggests getting bank statements.
- Home purchase records. The title company, escrow company or bank that handled the purchase.
- Improvements. The contractors who did the work, to see if they kept records.
- Photos. Pictures on a phone that show property before a loss.
Other third parties fit the same pattern. A vendor can reissue an invoice. A charity can resend a receipt or letter. An employer can send a copy of a pay statement. Each of these is a copy from the issuer, not a new estimate, and the checklist should say which it is.
A reconstruction built from memory or estimates is a different thing from a copy. A mileage log written months later from a calendar is a reconstruction. A list of supply purchases rebuilt from card statements, without the receipts, shows payment but not always what was bought. Mark each of these on the checklist so the firm knows which rows rest on originals, which rest on issuer copies and which rest on the client's after-the-fact summary. Publication 556 notes that a taxpayer seeking to shift the burden of proof in court must have kept the records the Internal Revenue Code requires, which is one reason the firm should know exactly what kind of record each row holds. How much weight a given substitute carries is a question for the representative, not the checklist.
Some audits concern a financial statement engagement rather than a tax return. Those use a different kind of list; the post on PBC request lists for audits covers it.