Carrier Overbilling on Detention Charges: How to Catch It

A broker in Dallas told us he ran the numbers on his last quarter and found $4,350 in detention charges he never should have paid. That's not a typo — forty-three hundred dollars in 90 days, spread across 212 loads. The charges ranged from $37 overages to a single invoice padded by $425. Every one of them looked normal at first glance. Carrier overbilling on detention charges is one of the most persistent margin killers in freight brokerage, and it's rarely dramatic enough to trigger suspicion on any single invoice. It adds up load by load, $75 here, $150 there, until you realize you've been bleeding money all quarter. The industry average sits around $187 per load in detention overcharges for brokers who don't audit consistently. This post breaks down the five most common ways carriers pad those invoices and tells you exactly what to check before you pay.

Why Detention Overbilling Is Getting Worse, Not Better

Detention charges have always been a gray area in freight. The shipper holds the truck too long, the carrier bills the broker, and the broker passes it along or eats the cost. Simple enough in theory. In practice, the timestamps are fuzzy, the rate con language is vague, and nobody has time to cross-reference every BOL against every carrier invoice at 4 PM on a Friday when you've got 30 loads still moving.

Here's what's changed: detention rates have climbed 18% since 2021 according to DAT data, with average hourly rates now sitting between $75 and $125 per hour depending on the lane and equipment type. Higher rates mean the dollar impact of even small time discrepancies has grown significantly. A carrier who rounds up by one hour at $100/hr used to cost you $50 in overbilling. Now that same rounding costs you $75 or more. Multiply that across hundreds of loads per month and you've got a five-figure annual problem.

The other factor: carrier billing systems have gotten more sophisticated. Many carriers now use automated detention billing that triggers based on geofence timestamps or ELD data. That sounds like it should make billing more accurate, and sometimes it does. But automated systems also generate charges based on rigid rules that don't account for the actual terms on your rate con. If the carrier's system defaults to a one-hour free time window and your rate con says two hours, you get billed for an extra hour on every load that detention applies to. These aren't malicious charges — they're systemic errors that repeat on every invoice until someone catches them.

The 5 Ways Carriers Pad Detention Invoices

After reviewing thousands of detention invoices across brokerages ranging from 100 to 5,000 loads per month, the same five patterns show up over and over. Some are intentional. Most are just sloppy billing that carriers have no incentive to fix because nobody pushes back. Either way, they cost you real money.

1. Inflated or Fabricated Arrival Times

This is the most common detention time billing error, and it's the easiest to miss. The carrier's invoice says the driver arrived at 06:00. The facility's check-in log or the BOL timestamp says 06:47. That 47-minute gap might not seem like much, but if the rate con allows two hours of free time, pushing the arrival earlier means detention kicks in sooner — or at all.

Here's a real example: A load delivering to a distribution center in Memphis had a two-hour free time window. The carrier's invoice listed arrival at 07:00 and departure at 11:30, billing 2.5 hours of detention at $75/hour for $187.50. The facility check-in log showed the driver actually arrived at 07:52. Real detention time? 1 hour and 38 minutes — which falls inside the two-hour free time. That's $187.50 in charges for zero actual billable detention. This happens more than you'd think.

What to check: Compare the carrier's stated arrival time against the facility check-in timestamp on the BOL or POD. If there's a discrepancy greater than 15 minutes, flag it. Also check ELD data if you have access through your TMS integration. A 15-minute gap might be the driver parking and walking in. A 45-minute gap is a billing error or worse.

2. Ignoring the Rate Con's Free Time Terms

Your rate con says two hours of free time. The carrier's billing system is set to one hour. Every load that triggers detention gets billed for an extra hour. This is the systemic error mentioned earlier, and it's the most expensive one over time because it hits every single detention invoice from that carrier — not just one.

We've seen cases where a broker moved 40 loads per month with a single carrier, roughly 25% triggered detention, and the carrier's system applied a one-hour free time default instead of the two hours on the rate con. That's 10 loads per month × 1 extra hour × $100/hour = $1,000 per month in overcharges from a single carrier. Over a year, $12,000 — from one billing system misconfiguration.

What to check: Pull up the rate con for every detention invoice. Confirm the free time listed matches what the carrier actually applied. If the carrier's invoice doesn't explicitly state the free time used in the calculation, ask for a breakdown. Any carrier who can't provide one is either disorganized or hoping you don't ask.

3. Rounding Up to the Next Full Hour

Many carriers bill detention in full-hour increments and always round up. Driver was detained for 2 hours and 12 minutes past free time? That's billed as 3 hours. At $100/hour, that rounding costs you $88 on a single load. Some carriers round up to the nearest half-hour, which is better but still means a 2:05 detention gets billed as 2:30.

The problem is that rounding policies are often buried in the carrier's tariff or standard terms, not in your rate con. If your rate con is silent on rounding, the carrier will apply their default — which is almost always in their favor. You won't even know it's happening unless you calculate the exact detention minutes from the timestamps and compare them to the billed amount.

What to check: Do the math yourself. Take the arrival time, add the free time window, then calculate the minutes from when free time expired to departure. Compare that to the billed hours. If there's a gap, you've found a rounding charge. Then check your rate con — does it specify rounding rules? If not, negotiate that language into your rate cons going forward. Fifteen minutes of rounding at $100/hour across 500 loads a year is $12,500.

4. Double-Billing Detention Across Multiple Stops

Multi-stop loads are a goldmine for detention overbilling. Here's how it works: a load has two delivery stops. The carrier experiences legitimate detention at Stop 1. Then at Stop 2, the driver arrives early, waits 45 minutes for an appointment, and the carrier bills detention for both stops.

The issue: waiting for an appointment window the driver arrived early for is not detention. Detention applies when a driver is held beyond the scheduled appointment time or beyond the free time window after a confirmed arrival. But carrier invoices often lump all wait time across all stops into a single detention line item without distinguishing between actual detention and early-arrival wait time.

A Midwest brokerage we talked to caught $2,100 in double-billed detention over two months, all from multi-stop loads with a single carrier. The carrier wasn't being dishonest — their invoice system totaled all non-driving dwell time across stops and labeled it detention. Nobody on the carrier side reviewed it. Nobody on the broker side questioned it. Until someone finally did the stop-by-stop math.

What to check: For any multi-stop load with detention charges, break down the timestamps at each stop individually. Verify that detention at each stop is calculated independently using that stop's appointment time and free time window. A single combined detention charge on a multi-stop load should always be questioned.

5. Charging Detention When the Delay Was Carrier-Caused

This one is less common but more infuriating when it happens. The driver shows up without the right equipment. The driver arrives outside the appointment window and the facility makes them wait for the next available door. The driver doesn't have proper lumper receipts and has to sort it out at the dock. In all these cases, the delay isn't the shipper's or receiver's fault — it's on the carrier. But the detention invoice comes to you anyway.

Proving this requires documentation: facility notes on the BOL, dock logs, appointment confirmation emails, or notes from your dispatcher. Without documentation, it becomes a he-said-she-said detention fee dispute that usually ends in a split-the-difference compromise, which means you're still paying half of a charge you don't owe.

What to check: Cross-reference the appointment time on the rate con or tender with the carrier's actual arrival time. If the driver arrived late and then was held, clarify whether the hold time was due to the late arrival (carrier-caused) or facility delays (legitimate detention). Keep dispatcher notes timestamped. They're your evidence in detention fee disputes.

What a Real Detention Charge Audit Looks Like

Knowing the five padding tactics is step one. Actually catching them on live invoices is step two — and it's where most brokerages fall short. Not because they don't care, but because the manual process takes too long when you're moving hundreds of loads a week.

A proper detention charge audit on a single invoice involves pulling the rate con, checking the free time terms, pulling the BOL or POD for facility timestamps, comparing those timestamps against the carrier's stated arrival and departure, calculating actual detention minutes, checking the billed hours against the real minutes, and verifying the hourly rate matches the rate con. That's seven steps per invoice. If 15% of your loads trigger detention and you move 500 loads per month, you're auditing 75 invoices. At 10 minutes each — and that's optimistic — that's 12.5 hours per month of audit work. For one billing coordinator, that's basically a day and a half gone every month just on detention.

This is why so many brokers either spot-check a random sample (and miss the systemic errors) or just pay everything under a certain dollar threshold (and reward carriers who keep their padding small). Neither approach actually stops the bleeding.

How to Build a Detention Audit Process That Actually Scales

You don't need a team of five billing coordinators to catch freight detention overcharges. You need a process that makes the right data easy to compare and flags discrepancies before payment goes out.

Start With Your Rate Cons

Every rate con should explicitly state: free time hours, detention hourly rate, rounding policy (or state 'billed to the minute'), whether detention applies per stop or per load on multi-stop shipments, and what documentation is required for the carrier to support a detention claim. If your rate cons are vague on any of these, you're giving carriers room to bill however they want. Tighten the language first. It's the cheapest fix you'll ever make.

Automate the Document Comparison

The bottleneck in detention auditing isn't the math — it's pulling the right documents and lining up the data points. When your billing coordinator has to open the rate con in one tab, the carrier invoice in another, the BOL scan in a third, and then manually type timestamps into a spreadsheet, errors happen and time evaporates.

Tools that extract data from freight documents — rate cons, BOLs, PODs, carrier invoices — and put the relevant fields side by side cut the per-invoice audit time from 10 minutes to under 2. Laneproof's document extraction tool at /tools/document-extract does exactly this: it pulls timestamps, rates, and terms from your documents so you can compare them without the tab-switching scavenger hunt. The goal is to spend your billing coordinator's time making decisions on flagged invoices, not hunting for data.

Real Numbers: What Catching Detention Overbilling Is Worth

Let's put actual dollars on this. These numbers are based on composites from brokerages running 300–1,000 loads per month.

Average detention incidence rate: 12–18% of loads. We'll use 15%. Average detention charge per incident: $225. Average overcharge per detention invoice (when present): $187. Percentage of detention invoices with some form of overcharge: 23%.

For a broker moving 500 loads per month: 75 loads trigger detention, roughly 17 of those have an overcharge, and the total monthly overcharge is approximately $3,179. Annually, that's $38,148 in detention charges that shouldn't have been paid. For a brokerage running on 12–15% margins, recovering $38K in overbilling is equivalent to winning $250K–$315K in new revenue. Except you don't have to make a single sales call to get it.

Even if your operation is smaller — say 200 loads per month — the math still works out to over $15,000 per year in recoverable overcharges. That's real money sitting in your carrier payment queue right now.

How to Dispute Detention Charges Without Burning Carrier Relationships

Catching the overcharge is half the battle. The other half is pushing back without turning every dispute into a relationship-damaging confrontation. Here's the approach that works.

Lead With Documentation, Not Accusations

When you dispute a detention invoice, never start with 'you overbilled us.' Start with 'we found a discrepancy in the timestamps — can you review?' Attach your evidence: the BOL timestamp, the rate con free time terms, and your calculation of the actual detention owed. Most carriers will correct the invoice without argument when the math is clear and the tone is professional.

The key is speed. Disputing an invoice 45 days after payment is awkward for everyone. Flagging it within 48 hours of receipt — before payment — is standard business. Carriers expect it. They respect it. And they're far more likely to adjust quickly because the invoice hasn't been booked to revenue yet on their end.

Track Patterns by Carrier

One overbilled detention invoice is a mistake. Five in a row from the same carrier is a pattern. Track your detention disputes by carrier. If a specific carrier consistently bills with one-hour free time when your rate con says two, that's a conversation to have with their billing department — once, clearly, with examples. Most of the time, it's a system configuration issue on their end, and they'll fix it once you point it out. If they don't fix it after being told, that tells you something about whether you want them in your carrier network.

Laneproof's reconciliation tool at /tools/reconcile can flag these patterns automatically by comparing carrier invoices against rate con terms across your full load history, so you're not relying on your billing coordinator's memory to notice that Carrier X has been rounding up on every invoice since March.

Your Detention Invoice Audit Checklist

Use this checklist on every detention invoice before you approve payment. It covers all five padding tactics and takes under 5 minutes per invoice once you have the documents pulled.

• Confirm the carrier's stated arrival time matches the facility check-in timestamp on the BOL or POD (within a 15-minute tolerance).
• Verify the free time window on the carrier's invoice matches the free time stated on the rate con — not the carrier's default terms.
• Calculate actual detention minutes from the end of free time to departure, and compare against the billed hours to catch rounding overcharges.
• For multi-stop loads, confirm detention is calculated per stop with separate timestamps, not lumped into a single combined charge.
• Check whether the driver arrived within the appointment window — if they arrived late and were held, determine whether the delay was carrier-caused.
• Verify the hourly detention rate on the invoice matches the rate on the rate con, not the carrier's standard tariff rate.
• Confirm the carrier attached supporting documentation (facility sign-in/sign-out, BOL notes, or ELD timestamps) as required by your rate con terms.
• Log every disputed invoice by carrier name, dispute reason, and dollar amount so you can identify repeat offenders and systemic billing errors.
• Set a 48-hour dispute window from invoice receipt — flag discrepancies before payment, not after.
• Review your rate con detention language quarterly and tighten any vague terms around free time, rounding, multi-stop rules, and required documentation.

Stop Paying for Time You Don't Owe

Carrier overbilling on detention charges isn't going to fix itself. Rates are climbing, carrier billing systems are getting more automated (but not more accurate), and every dollar you overpay on detention is a dollar straight off your margin. The five tactics covered here — inflated arrival times, ignored free time terms, aggressive rounding, multi-stop double-billing, and carrier-caused delay charges — account for the vast majority of detention overcharges brokers pay every month.

You don't need to audit every invoice manually. You do need a process that makes the right comparisons automatic and surfaces the discrepancies before your AP team cuts the check. Whether you tighten your rate con language today, assign someone to spot-check your top 10 carriers' detention invoices this week, or bring in a tool to handle the document comparison at scale — pick one and start. The money is already sitting in your payables. Go find it.