What demurrage is actually for
Demurrage is not, officially, a revenue line. It is a rationing tool. A railroad owns a finite fleet and a finite amount of track, and demurrage is the price signal that pushes cars to keep moving instead of sitting. That framing matters more than it sounds, because it gives you the standard the regulator itself applies.
The Surface Transportation Board has said plainly that demurrage rules and charges are not likely to be reasonable when they do not incentivize shippers and receivers to become more efficient in their use of rail assets. Read that again with a bill in front of you. If you could not have done anything differently, the charge is not doing the job it exists to do. That is not a loophole. It is the Board's own logic, and it is the backbone of most successful disputes.
None of which means you get to ignore the bill. It means you get to sort your charges into two piles: the ones that are telling you something true about your operation, and the ones that are not.
When the clock starts
Nearly every argument about demurrage is really an argument about a timestamp. Three concepts decide almost everything.
Actual placement
The car is spotted where you asked for it, on your track, at your spot. This is the clean case. You have the car, you control it, and the time is yours. Very few disputes start here.
Constructive placement
This is the expensive one, and it is where most contested bills live. Constructive placement is the status assigned when a car is available for delivery but cannot physically be placed at your facility because of a condition attributable to you, most commonly that there is no room on your tracks. The car goes to a hold track somewhere else, and the clock starts anyway.
The logic is defensible. If your yard is full, the railroad should not eat the cost of your congestion. The problem is that "attributable to you" does a lot of work in that sentence, and it is frequently applied to situations you did not create and could not see coming.
Free time and credit days
Free time is the grace period before charges begin, usually expressed in 24-hour periods or credit days. In most tariffs the clock commonly begins at 12:01 a.m. on the day following actual or constructive placement, which means the day of placement itself typically does not count against you.
Whether weekends and holidays count, and how many free days you get for a given commodity, varies by carrier and by tariff. That variation is not a footnote. It is where annual budgets quietly break, because the number someone memorized three years ago is not the number in force today.
Straight versus average agreements
How you are billed changes what good performance even looks like. There are two broad structures, and plenty of shippers are in the wrong one for their volume profile.
| Straight demurrage | Average agreement | |
|---|---|---|
| How it bills | Per car, per day, every day beyond free time | Cars released early earn credits that offset debits on cars held long |
| Suits | Low or irregular volume, predictable dwell | Steady volume with a mix of fast and slow cars |
| Where it hurts | One stuck car is simply a bill, with nothing to offset it | A bad month burns the credits you were banking on |
| What it demands | Fast turns on individual cars | Actual tracking, because the balance only works if someone is watching it |
An average agreement is not a discount. It is a bet that your fleet turns fast enough on average to carry the slow cars, and it only pays off if somebody is reconciling credits and debits against the carrier's numbers every cycle rather than at year end.
Four charges worth challenging
In its policy statement on demurrage and accessorial charges, the STB identified specific practices it considers unlikely to be reasonable. If you see these on an invoice, you have a real argument and not just a grievance.
- Constructive placement from remote locations. Charging you to move cars from a constructive placement point that sits far from your facility, when the distance itself was the carrier's choice.
- Missed switches. The railroad did not make a switch it was scheduled to make, and the resulting dwell landed on your invoice.
- Carrier-caused bunching. Cars are held upstream and then delivered in a clump your facility was never sized to absorb, which then triggers constructive placement on the overflow.
- Sudden changes to historical practice. Reduced switch days, thinner delivery frequency, or cut free time. The Board acknowledged a reduction in free time can sometimes be justified, but said the carrier must be able to produce evidence that it was warranted.
That last one is the most useful and the least used. A change in the pattern you have operated against for years is not automatically legitimate simply because it showed up in a tariff revision. The burden of showing it was warranted sits with the carrier.
What has to be on the invoice
You cannot dispute what you cannot see, which is why the billing rule matters as much as the policy statement. Since October 6, 2021, Class I carriers have been required to include minimum information on or with demurrage invoices, and to provide machine-readable access to it.
| Field | Why it is worth reading |
|---|---|
| Billing cycle | Anchors every other date and sets your dispute window |
| Waybill creation date | Shows when the shipment actually entered the system |
| Loaded or empty | Empties and loads often carry different free time |
| Commodity | Free time is frequently commodity specific |
| Original estimated arrival | The gap against actual arrival is where bunching shows up |
| Actual placement, per car | The timestamp the whole charge rests on |
| Release, per car | Closes the clock and exposes miscounted days |
| Interchange receipt date and time | On joint-line moves, identifies which carrier lost the time |
That last field is the one people overlook. On a joint-line move, the interchange timestamp is what lets you tell the difference between a car that sat in your yard and a car that sat for four days waiting to be handed between two railroads. Those are very different conversations, and without the timestamp you cannot prove which one you are having.
How we think about it
Buffer capacity is usually cheaper than demurrage, and almost nobody checks. Put your average monthly demurrage next to the cost of holding those same cars on private track where you control the clock. If the second number is smaller, you are paying a railroad to solve a problem you could solve for less, and you are paying it every month.
How to run a dispute that goes somewhere
Most disputes fail for boring reasons. They are late, they are vague, or they argue about fairness instead of facts. A dispute that works looks like this.
Pull the machine-readable file, not the PDF. You are entitled to it. A summary invoice hides exactly the per-car detail you need, and rekeying it by hand is how errors get introduced into your own argument.
Rebuild the timeline car by car. Placement, release, free time consumed, days charged. Do it in a spreadsheet. Most of the time the pattern surfaces on its own, and it is rarely spread evenly across the fleet.
Look at the seams. Interchange handoffs, weekends, the days around a service change. Time does not usually vanish in the middle of a clean move. It vanishes at handoffs, which is precisely why the interchange timestamp became a required field.
Bring evidence, not annoyance. Car numbers, timestamps, the specific practice you are challenging, and what you believe the correct figure is. A dispute that names a number gets resolved. One that expresses frustration gets acknowledged.
File inside the window. Every tariff sets a period for raising a dispute, and the STB has said those periods should be reasonable and balanced on both sides. Reasonable or not, missing it ends the conversation before it starts.
The short version
Demurrage punishes dwell, but it does not distinguish between dwell you caused and dwell that was handed to you. That distinction is your job to establish, and you can only establish it with timestamps.
So: know when your clock starts, know whether your billing structure fits your actual volume, read the interchange fields, and challenge the four practices the Board has already flagged. Then look hard at whether buffer capacity on private track costs less than the charges you have been absorbing. For a lot of shippers on this coast, it does, and the number is not close.
If you are looking at a demurrage line that has stopped making sense, we are glad to go through the actual invoices with you. That conversation is free and usually short.