Freight Audit
Freight Audit: A Plain-English Guide for Shippers Who Pay the Bills
Published May 29, 2026 · By Rob Eller
A freight audit is a line-by-line check of your carrier invoices against the contract you signed. Done right, the average shipper recovers 1.5 to 3 percent of total freight spend — money the carrier billed but was not entitled to under the agreement. The work is not glamorous: it is reading invoices against rate sheets, fuel tables, and Bill of Lading (BOL) notes, one line at a time. Your first audit with Eller is free.
Across the freight audit industry, Trax Technologies cites 5–7% average annual savings on enterprise transportation spend, AFS Logistics claims up to 8% recovery on freight audit programs, and ConData reports identifying $645M in carrier overcharges across its enterprise client base. Programs without an active audit firm routinely run 4–7% leakage; well-managed programs still recover 1.5–3%.
What's actually on a freight bill
A Less-than-Truckload (LTL) invoice usually arrives with six or seven line items. Each one is a place a carrier can quietly bill more than the contract allows. Learn the layout once and a lot of audit work stops feeling like detective work.
- Linehaul — the base rate for moving the freight from origin to destination, calculated off class and weight.
- Fuel surcharge (FSC) — a percentage applied to linehaul, indexed to the weekly DOE national diesel price.
- Accessorials — extra services like liftgate, residential delivery, inside delivery, limited access, or detention.
- Declared value — cargo liability coverage above the carrier's released-rate default (often $25/lb).
- Discount — the negotiated reduction off published tariff, applied to linehaul and sometimes accessorials.
- Minimum charge — the floor the carrier bills when the calculated rate falls below a contract threshold.
On any given invoice, four of those six numbers are formula-driven. That is what makes a real audit possible: math against contract terms, not opinion. The other two — accessorials and declared value — are document-driven: they should be on the BOL or in an authorization email, or they should not appear on the bill at all.
Most shippers see only the totals row at the bottom of the invoice and the carrier summary in their freight bill audit and payment (FBAP) platform. Neither view exposes the line-level math, which is where the recovery sits. A real audit re-derives every line from scratch using the same inputs the carrier should have used.
The seven errors a real audit catches
After reviewing several hundred carrier contracts, the same handful of billing errors show up across every shipper, every lane, every carrier. Here are the seven you should expect your audit to catch — with one concrete dollar example each.
- Rate error (class or weight-break miscoded). Carrier bills Class 100 on freight that ships as Class 70 per the National Motor Freight Classification (NMFC). On a 1,200-lb shipment, the gap can be $140 to $260 per invoice.
- Fuel surcharge miscalc (wrong DOE table week). Carrier applies the prior week's higher diesel-index percentage. On a $1,400 linehaul, a 1.4-point FSC error is roughly $20 per shipment — small per bill, four figures per month at volume.
- Accessorial without BOL authorization. A liftgate fee ($85) or residential delivery fee ($95) appears on the invoice with no matching note on the BOL and no email approval on file.
- Duplicate billing (same PRO billed twice). Same PRO number invoiced on two different statements weeks apart. Recovery is the full second invoice — sometimes $400 to $1,800.
- Minimum-charge override. Carrier bills a $215 absolute minimum on a shipment whose calculated rate would have been $148 under contract. The $67 gap is per shipment, repeated across hundreds of small parcels-of-freight moves.
- Discount not applied per contract. Master Rate Agreement (MRA) says 68 percent off published tariff; carrier bills at 64 percent. On a $1,000 gross linehaul, that is a $40 leak per invoice.
- NMFC reclassification without reweigh evidence. Carrier upgrades a shipment from Class 70 to Class 92.5 with no certified reweigh ticket or dimensional photo. Recovery is the full delta — commonly $180 to $400 per invoice on a mid-weight LTL load.
Worked example: $50M LTL+TL program, $1.7M recovered in 12 months
A mid-market manufacturer running roughly $50M annual freight spend across LTL and TL carriers. Audit runs against 12 months of paid invoices.
Aggregate recoverable identified: $1.71M (3.4% of total freight spend). Breakdown by category:
| Category | Recoverable | % of total recovery |
|---|---|---|
| Fuel-surcharge math errors (off-by-week index, exempt accessorials surcharged) | $480,000 | 28% |
| Accessorial billing without BOL authorization | $390,000 | 23% |
| NMFC reclassification without reweigh evidence | $260,000 | 15% |
| Minimum-charge clause misapplied (carrier default vs. negotiated formula) | $210,000 | 12% |
| Duplicate freight bills (same PRO across two billing cycles) | $165,000 | 10% |
| Contract discount tier underapplied to qualifying lanes | $120,000 | 7% |
| Detention disputed with receiver yard-log evidence | $85,000 | 5% |
For shippers running $100M+ annually, the same error-rate profile compounds to $3.4M–$5M of recoverable overcharges per year. For Fortune 500 enterprise shippers with $500M+ programs, ConData publicly cites cumulative audit identifications above $645M across its client base.
What your contract should say
Three clauses in the Master Rate Agreement carry most of the audit weight. If they are written loosely, the audit becomes a negotiation. If they are written tightly, the audit becomes math.
Minimum-charge clause
Fuel surcharge anchor
Accessorial authorization
Comparison: pre-audit vs. post-audit vs. second-look
| Audit type | When it runs | What it catches | Recovery rate | What it misses |
|---|---|---|---|---|
| Pre-audit | Before payment | Duplicates, obvious rate misapplications, missing PROs | 0.5–1.5% of spend | Fuel-index detail, reclass evidence, accessorial authorization gaps |
| Post-audit | After payment, within dispute window | All seven error categories, with documentation review | 1.5–3% of spend | Contracts the auditor was not given; appendix tariffs not on file |
| Second-look (post-post) | After a primary audit, on the same window | Items the first auditor closed, reclassifications, fuel-table edges | 0.3–0.8% of spend | Pre-payment timing protections; reweigh disputes already settled |
Copy-paste these into your next QBR or contract review
- "For the past 90 days, can you send the DOE diesel-table week reference used to set FSC on each invoice?"
- "For any invoice where a reclass was applied, please provide the certified reweigh ticket or dim photo on file."
- "What is your written process for capturing accessorial authorization, and where is that authorization stored?"
- "Please send a 12-month report of duplicate PROs flagged and credited — broken out by month."
What we can't tell from the bill alone
Audits have limits, and an honest auditor names them up front. A class dispute usually needs reweigh evidence the carrier may decline to share — a written reweigh policy in the MRA helps. Detention claims need driver-app GPS records or yard logs that originate with the carrier or the receiver. And many MRAs reference appendix tariffs — UPS GRI updates, an NMFC item-list, or a fuel matrix — that we need a copy of before we can fully audit the bill. When evidence is unavailable, we mark the line "evidence-gated" rather than disputing it on weak ground.
A few more honest limits: pricing-program tier discounts on parcel carriers reset every revenue period, so an audit that runs more than a quarter behind can miss the active tier. Mode-mix changes — the day your team moves from LTL to truckload on a lane — can hide a contract violation behind a category shift in your spend report. And spot-quote loads booked outside the MRA do not have a contract to audit against; the recourse there is the spot confirmation email, not the rate sheet.
How Eller Audit handles this
We run every invoice line against the actual signed MRA, the active DOE fuel table for the ship week, the carrier's accessorial tariff in effect, and the BOL on file. Findings come back in a plain-English report with the contract clause, the math, and the recommended dispute language already drafted — ready to send to your carrier rep, no rework required. After the first free audit, pricing is performance-based: we are paid a share of what we recover, so we do not get paid if you do not. The first audit is on us so you can compare what we find against what your current process catches, side by side, before any commercial decision.
Frequently asked questions
How long do I have to dispute a freight overcharge?
49 USC 13710 allows 180 days for carriers and shippers to challenge undercharges or overcharges in most cases, but contract terms can extend or restrict this window. Read the audit clause in your Master Rate Agreement before relying on the statutory default.
What's the average recovery rate on a freight audit?
1.5 to 3 percent of audited spend is typical. The rate runs higher for shippers without an active audit program in place — sometimes 4 to 6 percent on the first pass — and lower for shippers already running disciplined pre-audit and post-audit cycles.
Do you audit parcel too?
Yes. We audit UPS and FedEx invoices, including Guaranteed Service Refund (GSR) eligibility on late deliveries and dimensional-weight errors. Parcel audits run on a different cadence than LTL because the carrier dispute windows are shorter — sometimes 15 days for GSR claims.
Can you audit invoices we already paid?
Yes. A post-audit recovers overcharges from paid invoices going back the dispute window allowed by your contract or by 49 USC 13710, whichever applies. Most shippers we work with have 180 days of paid invoices that are still in the dispute window on day one.
Related reading
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