An MCS-90 is a one-page endorsement attached to your truck's liability policy, and it does one job: it promises that anyone your truck injures, and any property your truck damages, gets paid even if your own insurer would otherwise deny the claim. It exists to protect the public. Your business gets no coverage from it. For a tank truck hauling gasoline or diesel, the federal rules set that guarantee at a minimum of $1,000,000, and it climbs to $5,000,000 for a few trucks carrying listed hazardous materials in bulk.
What the MCS-90 actually is
The full name is the Endorsement for Motor Carrier Policies of Insurance for Public Liability under the Motor Carrier Act of 1980. The FMCSA requires it. Once it is attached to your auto liability policy, your insurer agrees to pay any final court judgment against you for bodily injury, property damage, or environmental restoration caused by the negligent operation of your vehicles.
The word that matters is any. The endorsement responds even when the truck involved was left off the policy schedule, even when the driver was hauling a load he was not supposed to, and even when a pollution exclusion in the policy would normally block the claim. If a member of the public wins a judgment against you, the MCS-90 makes sure that person is paid up to the federal minimum. It is a backstop written for the injured party, not for the carrier.
The federal minimums under 49 CFR 387.9
The dollar figures live in a short table at 49 CFR 387.9. They apply to for-hire and private carriers running vehicles over 10,000 pounds, and to any vehicle hauling placarded hazardous materials regardless of weight. Because a jobber running its own tankers is a private carrier of hazmat, these rules reach your own fleet, not just the common carriers you hire.
- $750,000. General freight and other nonhazardous property.
- $1,000,000. Oil and petroleum products, including gasoline, diesel, and heating oil, plus most hazardous materials.
- $5,000,000. Certain listed hazardous substances hauled in cargo tanks larger than 3,500 water gallons, bulk explosives and poison gas, and highway route controlled radioactive material.
Why petroleum lands at $1,000,000
Gasoline, diesel, and heating oil are Class 3 flammable liquids and count as oil listed in the hazardous materials table, so a standard fuel tank truck sits on the $1,000,000 line. Propane behaves the same way. LP-gas is a Division 2.1 flammable gas, so bobtails and transports carry that same $1,000,000 minimum, a point worth keeping in mind if you run a propane operation alongside the fuel side.
The $5,000,000 tier is narrow. It is reserved for listed hazardous substances above threshold quantities and a handful of high-risk cargoes. Most gasoline and diesel jobbers never touch it. A carrier moving specific bulk chemicals does, and it is worth confirming your product mix against the hazmat table rather than assuming $1,000,000 always applies.
The catch: it pays the public, then bills you
The MCS-90 is not extra insurance for your company. If your insurer pays a claim under the endorsement that your policy would not otherwise have covered, the endorsement includes a reimbursement clause, and you owe that money back. So the MCS-90 is a promise to the public that runs through your own checkbook. That is the reason it is no substitute for well-built auto liability limits and a real environmental policy. Lean on the endorsement alone and a single tanker rollover can turn into a seven-figure bill you personally have to repay.
How it shows up in your filings
Two things live in two places. The MCS-90 endorsement itself stays with your insurance policy. Separately, your insurer files a Form BMC-91 or BMC-91X with the FMCSA as proof you meet the minimum. Keep a copy of the endorsement where both dispatch and the back office can pull it fast, because a compliance review or a claim adjuster will ask for it, and a driver may be asked during a roadside inspection. Loose insurance documents are one of the small back-office gaps that good jobber software is built to close, storing certificates and endorsements alongside the driver files they belong with.
What this means for the back office
Hazmat auto premiums are a fixed cost that rides on every gallon you move, and they belong on the list of quiet items in where fuel margin leaks. When money is involved, precision pays: confirm the endorsement is current at every renewal, confirm the BMC filing is active with the FMCSA, and confirm your primary limits are high enough that you are never relying on the statutory floor to make an injured party whole.
The MCS-90 also earns a line on any deal sheet. If you are buying or selling a jobber business, the endorsement, the BMC filing, and the loss history behind them are standard due diligence. A lapse or a large past payout tells you something about how the fleet has been run, and it can move the price.
Questions people ask
Does the MCS-90 apply if I only haul within my own state?
For placarded fuel loads, yes. The federal financial-responsibility rules in 49 CFR 387 cover hazardous materials moved in intrastate commerce, not only interstate freight, so a gasoline tanker running local routes is still in scope. Your state may add its own filing or a different limit on top of the federal one, so check the rules where you operate.
If I hire a third-party carrier to move my product, whose MCS-90 covers the truck?
The carrier operating the vehicle carries its own endorsement and filing. Before you tender loads to a for-hire hauler, verify their FMCSA financial-responsibility status is active. If they are running uninsured or lapsed, an incident with your product on board can still pull you into the dispute.
Does the MCS-90 pay to replace the fuel I lose in a wreck?
No. The endorsement covers injury and damage to other people and their property. The value of the product on the truck is cargo, and that is covered by a separate motor truck cargo policy. Many jobbers assume one policy handles both and find out otherwise at the worst possible time.
Is $1,000,000 really enough for a serious fuel spill?
Treat it as the legal floor, not a target. A tanker rollover that closes a highway and contaminates groundwater can run well past a million dollars once you add cleanup, third-party claims, and legal defense. Most established carriers hold higher primary auto limits plus an umbrella and a dedicated environmental policy above the statutory minimum.