How to Audit Your Freight Invoices (Step-by-Step)

Why Audit Your Freight Invoices?

If you're shipping LTL freight and not auditing your invoices, you're almost certainly overpaying. Studies consistently show that 5-8% of LTL invoices contain errors — and they're almost always in the carrier's favor.

Here's a step-by-step guide to auditing your freight invoices, whether you do it manually or use a tool like FreightGuard.

Step 1: Gather Your Rate Agreements

Before you can audit anything, you need to know what you should be paying. Collect your rate agreements from every carrier you use. Key items:

• Base rates by lane (origin/destination zip code ranges), freight class, and weight break
• Accessorial rates — liftgate, residential delivery, inside delivery, limited access, etc.
• Fuel surcharge table — the DOE diesel index brackets and corresponding surcharge percentages
• Effective dates — rates change, make sure you're comparing against the right agreement

Step 2: Export or Collect Your Invoices

Get your invoices in a format you can work with:

• CSV export from your carrier's online portal (preferred — structured data)
• PDF invoices — need to be parsed into structured data first
• At minimum, you need: PRO number, ship date, origin zip, destination zip, weight, freight class, base charge, fuel surcharge, accessorials, and total charge per shipment

Step 3: Compare Base Rates

For each line item, look up the applicable rate from your rate agreement:

• Match the origin and destination zip codes to a lane in your agreement
• Find the correct freight class
• Find the correct weight break
• Calculate: (weight / 100) × rate per CWT = expected base charge
• Compare against the invoiced base charge

Any difference is a potential overcharge.

Step 4: Verify Fuel Surcharges

• Find the DOE National Average Diesel Fuel Price for the week the shipment moved
• Look up the corresponding bracket in your fuel surcharge table
• Calculate: base charge × surcharge percentage = expected fuel surcharge
• Compare against the invoiced fuel surcharge

Step 5: Check Accessorials

For every accessorial charge on the invoice:

• Verify the accessorial type exists in your rate agreement
• Verify the amount matches your contracted rate
• For residential delivery surcharges specifically — validate the delivery address. Is it actually residential?

Step 6: Check for Duplicates

Search for:

• Duplicate PRO numbers across different invoices
• Shipments with identical origin, destination, date, weight, and total on different invoices

Step 7: File Disputes

For every overcharge found:

• Document the discrepancy: what was invoiced, what it should be, the difference, and why
• Reference your rate agreement
• Submit a formal dispute to the carrier's billing department
• Track the dispute through resolution

Step 8: Check Weight Breaks

Sometimes bumping your shipment weight up to the next weight break tier actually results in a *lower* total charge. For example, a 480 lb shipment at the 500 lb rate might be cheaper than the 200-499 lb rate. Carriers won't tell you this — but you should check every shipment.

The Easier Way

Doing this manually across hundreds of shipments per month is time-consuming. That's why we built FreightGuard — upload your invoices, enter your rate agreements, and the system runs all these checks automatically. With 17 dedicated AI parsers, weight break optimization, and a savings analytics dashboard, you get a complete view of your freight spend.

Start auditing → — See your first results within 24 hours of uploading invoices.