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You can ship most everyday liquids if you pack them assuming a leak: tighten and tape every cap, seal each bottle in its own zip bag with absorbent padding, and use a sturdy corrugated box. Flammable, corrosive, and pressurized liquids are banned or restricted by every major carrier.
| Type of liquid | Can you ship it? | What matters most |
|---|---|---|
| Sauces, syrups, shampoo, lotion, juice | Yes, with careful packing | Leak-proof inner bag plus absorbent padding |
| Wine and other alcohol | US: state rules and licenses; Canada: generally no via post | Check recipient province/state rules first |
| Perfume, nail polish, hand sanitizer | Restricted: flammable | Ground only where allowed; special labels needed |
| Bleach, cleaners, acids | No: corrosive | Banned from ordinary parcel services |
| Aerosol cans | Restricted: pressurized | Caps taped or latched; ground services only |
Start here, because the packing method does not matter if the contents are banned. Gasoline, solvents, lighter fluid, and most laboratory chemicals are flatly prohibited in ordinary parcel mail. Aerosols and anything marked flammable sit in a restricted middle zone: some carriers take them by ground with special handling labels, others refuse them outright. Alcohol is its own maze. In the US, shipping wine or spirits depends on the laws of both states involved, and ordinary people usually need a licensed retailer or winery to send it legally. In Canada, shipping alcohol by mail is broadly off limits between private individuals. When you are unsure, check the carrier's prohibited-items list before you buy a box.
Pack like the bottle will break, because somewhere on a conveyor belt, that is exactly what happens. The single best habit: give every container its own sealed bag. Squeeze the air out of a zip-top freezer bag, seal the bottle inside it, and repeat for each bottle. If one leaks, the damage stops at that bag.
Caps cause more leaks than cracked bottles. Screw each cap down hard, then wrap a strip of electrical or packing tape around the seam where the cap meets the neck. Tape is cheap insurance against caps that vibrate loose in transit. For flip-top or pump bottles, tape the pump down and put the bottle in its bag too.
Then add absorbent padding around the bagged bottles: crumpled newspaper, bubble wrap, or paper towels. The padding serves two jobs. It cushions the glass or plastic, and it soaks up liquid if the bag fails. Fill the box so nothing moves when you shake it. A rattling bottle is a broken bottle.
Use a rigid corrugated box, not a padded mailer. Mailers flex, and flexing cracks caps and seams. Stand bottles upright and brace them so they cannot tip: cardboard dividers, rolled paper, or custom inserts all work. Tape every seam of the box with packing tape, top and bottom.
Marking the box "THIS SIDE UP" or drawing upward arrows is worth doing, but treat it as a request, not a guarantee. Parcels tumble on conveyors no matter what the arrows say. That is why the inner bag matters more than the marking. Keep the shipping label on the largest flat side, away from seams, so barcode scanners read it on the first pass.
Yes, and the difference that catches people is liquids in the Canada Post network. Canada Post prohibits corrosive, flammable, and toxic liquids outright, and restricts aerosols. Non-flammable, non-hazardous liquids like cosmetics, soaps, and packaged food sauces are fine when packed to survive the trip, which is the same standard every carrier uses: no leaks, no damage to other parcels.
The other Canadian wrinkle is winter. If you are shipping liquid to or within Canada between roughly November and March, remember that water-based liquids can freeze in unheated trucks and sortation sheds. A frozen bottle can crack, then leak when it thaws at the recipient's door. Wrapping in insulation and choosing a faster service reduces that risk, but for anything freeze-sensitive, consider whether the timing is worth it.
One more non-obvious rule: carriers can refuse or surcharge a parcel that leaks in their system. A leak that damages someone else's package can come back to you as a claim. That is the real cost of a loose cap, and it is entirely avoidable with ten minutes of packing.
Ready to ship it? Get a shipping label with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and get your label.
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