Shipping Hazmat From a Marketplace: Lithium Batteries, Perfume, Aerosols and the USPS Fee

USPS charged me $50 hazmat wrongfully, a seller wrote on the eBay Community this week, and the thread filled within the hour with sellers who had been charged the same and did not know why. Most of them were shipping something ordinary: a bottle of perfume, a phone case with a battery in it, a can of dry shampoo. Since 12 July 2026, as reported, a parcel with hazmat in it that was not declared as hazmat draws a $50 noncompliance fee from USPS on top of the postage, and the fee lands on the account that bought the label, weeks later, through whichever marketplace or shipping tool sold it.

This is what counts as hazmat to the Postal Service, which services will carry it, how it is declared on the labels the marketplaces sell, and what a dispute needs when the fee was wrong. It applies to a seller on any channel who ships their own parcels; Amazon's own fulfilment has its own hazmat rules, which are a different subject.

Perfume, nail polish, aerosols, hand sanitiser, mouthwash and lithium batteries are all hazardous materials to USPS, whatever the size of the bottle, because the contents decide it. Declared hazmat can be shipped: there is no handling fee on Ground Advantage and Parcel Select and $7.50 on Priority Mail and Priority Mail Express. Undeclared or mislabelled hazmat is what costs, with a $50 fee per package, as reported, charged from 12 July 2026 to the account that bought the label.

More than most sellers expect. USPS's own examples are lithium batteries, whether in a device, packed with one or on their own; perfumes and colognes, which are flammable; nail polish; aerosols of every kind, from hairspray to spray paint; hand sanitiser and anything else alcohol based; mouthwash; and household products with flammable, corrosive or pressurised ingredients. The test is the product's contents, not its packaging or its size: a 30ml bottle of perfume is hazmat, and so is a single AA lithium cell.

The categories that trip sellers up are the ones where the product is ordinary and the ingredient is not. Cosmetics, personal care, fragrance, electronics with batteries, and cleaning products account for most of the fees in the threads, and a store in any of those categories is a hazmat shipper whether it knows it or not.

Most consumer hazmat cannot fly, so it travels by ground: USPS Ground Advantage and Parcel Select, where, as reported, declared hazmat carries no handling fee. Priority Mail and Priority Mail Express accept a narrower set of hazmat, and declared hazmat on those services carries a $7.50 handling fee per package. Some hazmat is not mailable at all on any service, and the carrier's rules, not the seller's judgement, decide which.

Lithium batteries have their own rules under USPS's Publication 52. New devices with batteries installed ship under limits on quantity and cell size, with the required markings. Used, damaged or defective devices containing or packed with lithium batteries ship by ground only and must carry the specified marking, because a damaged cell is the one that starts fires. A returned phone going back to a seller is that case, and it is the case most often shipped wrong.

Sellers who send stock to Amazon meet the same products under a different process: Amazon's dangerous goods review, which decides whether a product can enter its fulfilment centres and how it is stored there.

The review comes first. Products Amazon identifies as possibly hazardous are held from inbound shipments until reviewed. The seller supplies a safety data sheet for the product, or an exemption sheet showing why it is not regulated, and Amazon classifies it.

Safety data sheets have to be right. The sheet has to be for the exact product, from the manufacturer, current, and complete in the sections Amazon reads. A generic sheet, an old version or one for a similar product is the commonest reason for a review to stall.

Classified products are stored apart. Flammable products and aerosols are kept in dedicated storage with its own capacity limit, separate from standard stock. Room in standard storage does not help them, so they need their own line in the capacity plan.

Plan the time. A review takes days at best, and a product held at inbound is stock earning nothing. Submit documents when the product is first listed, not when the shipment is ready.

The other compliance questions a new product meets before it ships are in Amazon private label, and what it actually takes.

The fee is for hazmat that was not declared, so the fix is the declaration, and every label tool has one. On eBay's shipping labels there is a hazmat option when the label is bought, which restricts the services offered to the ones that carry it and adds the marking. Amazon's Buy Shipping asks the same question and does the same. Shopify Shipping, the independent services that sell discounted postage labels, and the other label tools carry the declaration through to the carrier's system. A label bought without the declaration, for a parcel that contains hazmat, is the parcel that draws the fee when USPS finds it, which it does by scanning, by the box's own markings, and by inspection.

The declaration has to be right at the product level, not the order level: the SKU carries the hazmat flag, and every label for that SKU is bought with it. A seller who declares by memory declares wrongly on the day the packing bench is busy, and the fee arrives a month later.

Lithium batteries account for more hazmat confusion than any other product type, because the same battery can be shipped in different ways depending on how it is packed and how large it is.

How the battery travels. A battery installed in the device it powers, a battery packed in the box with a device, and a battery sold on its own are treated differently, with the most restrictions on batteries shipped alone. The listing and the packaging should make clear which applies.

Lithium ion or lithium metal. Rechargeable lithium ion batteries and non rechargeable lithium metal batteries fall under different rules, and the label has to say which.

Size matters. Lithium ion batteries are rated in watt hours and lithium metal batteries by lithium content. Larger batteries face tighter limits and, above certain sizes, full dangerous goods shipping rather than the simpler consumer rules.

The test summary. Lithium batteries are tested under the UN 38.3 standard, and manufacturers are expected to make a test summary available. Ask for it from the supplier before ordering; marketplaces and carriers may ask for it, and a supplier that cannot produce one is a warning sign.

Damaged batteries are different again. A battery returned damaged or swollen cannot simply be shipped back or resold. Have a plan for disposing of damaged batteries safely before the first one arrives.

One warning in the carrier's guidance is worth its own paragraph, because it is the wrongfully charged fee in most of the threads. A reused box that still carries old hazmat markings, a lithium battery label from the box's first life, a printed warning from the manufacturer, can draw the noncompliance fee even when the contents are not hazardous, because the marking says hazmat and the label says none. Sellers who reuse supplier cartons, which is most small sellers, are shipping in boxes with markings they never read. Cover them or do not reuse them.

For hazmat that is declared, the marking on the box is part of the declaration, and it has to match the label. The tools print it; the packer has to apply it on the face of the parcel the carrier scans.

The fee arrives as an adjustment on the account that bought the label, which for most marketplace sellers means through the marketplace's own shipping billing, the same route as the carrier's other after the fact charges, which Amazon seller fees explained places in the fee stack for one marketplace. The dispute goes back the same way: through the marketplace's or the tool's support, with the tracking number, a photograph of the parcel and the product, and the reason the parcel was not hazmat. A parcel that was hazmat and was undeclared is not disputable; the fee is the rule working.

The evidence that wins is the product's own documentation: an ingredient list without a flammable component, a battery free product listing, a box photograph without markings. Sellers who keep a photograph of every parcel at the bench, which is a habit the item not received claims on eBay already reward, have the evidence before the fee arrives; the Top Rated Seller requirements are what that habit protects on eBay.

USPS's fee is the change that started the threads, but a seller using more than one carrier, or shipping abroad, meets the same products under different rules.

Private carriers. UPS and FedEx carry many consumer products that count as hazardous, such as perfume and aerosols, under simplified rules for limited quantities by ground. Fully regulated dangerous goods generally need an agreement with the carrier and trained staff to prepare them. Check each carrier's rules for the products sold before choosing it for them.

Air versus ground. Much consumer hazmat cannot travel by air, or only in small quantities under strict packing. Express services that rely on air may refuse products that ground services accept, which affects the delivery promise a listing can make.

International parcels. International mail and courier services restrict hazmat far more than domestic ground services, and many common items, such as perfume and spare lithium batteries, cannot be sent abroad by post at all. A store offering worldwide shipping should exclude restricted products from international delivery in its shipping settings.

Write the rules into the system. Flag hazmat products in the store's catalogue and shipping profiles so they are offered only the services and destinations that can carry them. A rule set once in the system is followed on every order; a rule that relies on the packer remembering is not.

Go through the catalogue once and flag every SKU that is hazmat by USPS's list. Set the flag in every channel's listing or shipping profile so the label tool declares it. Buy ground services for it. Strip or cover markings on reused boxes. Keep a parcel photograph. And read the shipping adjustments monthly, because a fee that arrives and is not read is a fee paid twice, once in money and once in the next parcel packed the same way. For the brands we run across channels under marketplace management, the hazmat flag is set on the SKU on the day the product is listed, and the fee stack it sits inside, from postage to surcharges, is the one the eBay inventory management article sits beside, where the same parcel is sold on more than one channel. The multi channel stock behind it is the subject of the multi channel fulfilment article.