Trucking companies deal with two types of audits. Financial audits from the IRS focus on income, expenses, and tax compliance. DOT audits focus on safety and operational compliance. You need documentation ready for both.

For financial audits, start with income documentation. Keep every load sheet, rate confirmation, broker settlement statement, and invoice. If you’re paid by a carrier or broker, those settlement statements show gross pay, deductions, and net pay. The IRS wants to see that your reported income matches what you actually received.

Fuel records are critical for trucking businesses. Save every fuel receipt showing date, location, gallons purchased, and amount paid. These receipts support both your expense deductions and your IFTA filings. Fuel cards help because they generate detailed reports, but keep the underlying receipts anyway.

IFTA documentation requires mileage logs broken down by state or province. You need to show where you drove, not just total miles. Your ELD data helps here, but maintain separate mileage records that clearly show jurisdictional breakdown. Auditors will compare your reported miles to fuel purchases to check if the numbers make sense.

Maintenance and repair records serve double duty. They support expense deductions on your taxes and prove vehicle maintenance compliance for DOT. Keep invoices for all repairs, oil changes, tire purchases, and parts. Note which truck or trailer each expense applies to.

Heavy Vehicle Use Tax documentation matters if you operate trucks over 55,000 pounds. Keep copies of Form 2290 filings and proof of payment for each vehicle. This comes up in both IRS and DOT audits.

Equipment depreciation requires purchase documents, loan agreements, and records of any improvements. The IRS wants to verify your depreciation schedule matches actual purchase prices and dates. If you bought a used truck, keep the bill of sale showing what you paid.

Per diem records need documentation if you claim the per diem deduction. Keep logs showing days away from your tax home, where you were, and why. The IRS has challenged per diem deductions that lack supporting documentation.

Payroll records for company drivers should include W-4s, pay stubs, tax deposits, quarterly filings, and year-end W-2s. If you use owner-operators, keep contracts, 1099s, and payment records. The distinction between employee and contractor matters and the IRS looks closely at trucking companies for misclassification.

DOT audits require driver qualification files with applications, licenses, medical certificates, driving records, and road test documentation. You also need hours of service logs from your ELD, vehicle inspection reports, and drug and alcohol testing records. These have different retention periods than tax records.

Retention periods vary by document type. Keep tax-related records for at least seven years. The IRS can audit up to six years back in certain situations. Driver qualification files need to stay on hand for three years after a driver leaves. Hours of service records require six months. Vehicle inspection reports stay until the next annual inspection.

The practical approach is to keep everything for seven years unless you know a specific shorter period applies. Storage is cheap compared to scrambling during an audit because you threw something away too early.

Organize records by year and category so you can find what auditors ask for. A bookkeeper near Gentry who understands trucking can help you set up systems that capture everything from the start rather than reconstructing records when an audit notice arrives.