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Home > Guides > Shipping in Freezing Weather
Cold ruins shipments three ways: liquids freeze and burst their containers, lithium batteries lose charge and can be damaged, and condensation forms when a frozen parcel warms up. Pack with insulation, cushion against freezing, and choose faster services so parcels spend less time in unheated trucks.
| Risk | What happens | How to protect it |
|---|---|---|
| Liquids (wine, cosmetics, sauces) | Water-based liquids expand as they freeze and crack bottles or burst seals | Insulated box plus packing material; consider holding the shipment until a warm spell |
| Lithium batteries | Capacity drops in the cold; charging a frozen battery can damage it permanently | Keep the device off; warn the recipient not to charge it until it reaches room temperature |
| Electronics | Condensation forms inside when a cold device enters a warm room | Seal the item in a plastic bag before boxing; let it warm up sealed for several hours |
| Wooden instruments and furniture | Rapid temperature swings cause cracking and warping | Double-box with insulation; allow gradual warm-up on arrival |
Cold enough to freeze. Sorting facilities, cargo holds, and delivery trucks are not heated, and a parcel left on a porch or in a metal community mailbox can sit below freezing for hours or days. People assume parcels stay near room temperature inside the system; they do not. Plan as though your package will spend its entire trip at the outside temperature.
That assumption changes the packing. A single cardboard box offers almost no insulation. A snug inner box with crumpled paper or foam around it buys the contents real thermal buffer time, because still air trapped in packing material slows heat loss. For genuinely temperature-sensitive contents, insulated shippers with foam walls exist, and cold packs can be swapped for nothing at all: in winter, the cold pack is the weather.
Aerosols are the big one. Pressurized cans in extreme cold can behave unpredictably, and most carriers restrict or prohibit them outright. Fresh flowers, live plants, and anything that must stay above freezing are close behind: no amount of packing makes a three-day trip through a cold snap safe for a living thing. Wine and craft beer shipments freeze, push corks, and leak. If the contents cannot survive a freeze, either wait for milder weather or pay for the fastest service so the parcel spends minimal time in the cold.
Check the carrier's prohibited and restricted lists before you ship. Canada Post, USPS, UPS, and FedEx each publish theirs, and temperature restrictions are usually listed alongside the usual suspects like flammables.
Yes, in two ways. First, tape. Standard packing tape loses adhesion in extreme cold, so use quality packing tape and apply it generously, with full H-seals on both the top and bottom of the box. Second, the label. Thermal-printed labels can fade if they get wet from snow or condensation, so cover the label with clear packing tape, leaving the barcode scannable. A smeared barcode can stall a parcel at a sorting facility.
Also protect the outside: a plastic mailer bag over a cardboard box keeps melting snow out. It costs almost nothing and prevents the soggy-box scenario where the recipient gets your item in a disintegrating carton.
The single most useful line you can add to a winter shipment: "If this parcel is very cold on arrival, let it warm to room temperature before opening or charging." Electronics with lithium batteries should not be charged cold. A few hours on a counter solves it. For liquids, inspect for leaks before opening, and for anything with a seal (cosmetics, food), check that the seal is intact after thawing.
If you are shipping within Canada in winter, you can get a Canada Post Xpresspost label through your AI assistant with LetterAgent: you approve the exact quoted price and receive a label PDF. Xpresspost's speed is itself a winter advantage, since the parcel spends fewer nights in unheated facilities. Canada-only, 5 kg max.
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.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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