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Home > Guides > Shipping frozen food
LetterAgent can't handle this one: its labels are Canada Post Xpresspost flat-rate, up to 5 kg, for ordinary parcels, and frozen food needs insulated packaging plus dry ice, which carriers restrict. In general, frozen food ships fine with the right setup: an insulated container, enough dry ice to last the whole trip, and the fastest service you can get.
Because the cold doesn't last. A standard cardboard box has almost no insulation, so frozen food starts thawing within hours, and meltwater soaks through the box and everything around it. Thawed-and-refrozen food is a food-safety problem, not just a quality one: once food rises above safe temperatures for long, it should not be refrozen, and you can't tell from the outside how warm it got. Regular ice is worse than useless here: it melts into water that pools in the box, while dry ice sublimates into gas and leaves nothing behind.
| Component | What it does | Notes |
|---|---|---|
| Insulated container | Holds the cold in: a foam cooler or an insulated box liner | Sits inside the outer shipping box, not instead of it |
| Dry ice | Keeps everything frozen solid for the whole trip | Solid carbon dioxide: handle with gloves, it burns skin on contact |
| Sturdy outer box | Protects the insulation and takes the handling abuse | Double-wall corrugated if the contents are heavy |
| Venting | Lets the carbon dioxide gas escape as the dry ice sublimates | Never seal a dry-ice package airtight: pressure builds |
| Dry-ice marking | Tells the carrier what's inside | Required by carriers that accept dry ice; check their dangerous-goods page |
Dry ice is regulated as a dangerous good when it flies, because it sublimates into carbon dioxide gas: in a sealed container, pressure builds, and in an enclosed cargo hold, the gas displaces air. Carriers that accept it require the package to vent, to be marked as containing dry ice, and to stay under quantity limits. The rules differ between ground and air and between carriers, so check the specific carrier's dangerous-goods page before you pack, not after. Some carriers restrict dry ice to certain services or ban it outright. Gloves are non-negotiable when handling it: dry ice burns skin on contact, and newspaper or a towel is not a substitute for proper handling.
Early in the week, with the fastest service available. A box shipped Monday arrives before the weekend; a box shipped Thursday can sit in a warehouse over Saturday and Sunday, and no reasonable amount of dry ice covers that. Build in a buffer day: if the carrier quotes two days, pack dry ice for three. Tell the recipient when it's coming so it doesn't sit on a porch thawing after delivery: frozen food has a short grace period once it arrives, and a doorstep in the sun burns through it fast.
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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