How to Ship Food: Mailing Perishable, Frozen and Shelf-Stable Food Safely (2026)

Updated October 2026.

Yes, you can ship food, including perishable and frozen food, through USPS, UPS and FedEx: the carrier moves the box, but your packaging has to keep the food at a safe temperature the entire way. In practice that means an insulated container, enough gel packs or dry ice for the full transit time, a 1-2 day service for anything perishable, and dry-ice markings that follow carrier and federal rules.

This guide covers what each type of food needs, the USPS dry-ice limits, the temperature target your shipment has to hit, and how food brands keep shipping costs under control.

Can you mail food?

Yes. Shelf-stable food can go by any service, while refrigerated and frozen food needs insulation, coolant and fast transit, because USPS does not offer refrigeration. USPS recommends Priority Mail or Priority Mail Express for items that must stay cold, and it notes that insurance will not pay for spoiled food even when the package arrives on time (source: USPS, How Do I Keep My Mailed Item Cold or Refrigerated).

Perishable food is anything that spoils or becomes unsafe without refrigeration: meat, seafood, dairy, fresh baked goods with dairy fillings and prepared meals.

What temperature does shipped food need to arrive at?

Perishable food should arrive frozen, partially frozen with ice crystals still visible, or at least refrigerator-cold: below 40°F measured with a food thermometer. USDA advises recipients not to eat perishable food that arrives above 40°F and to ask the sender for a replacement (source: USDA, Mail Order Food Safety). Plan coolant for the full scheduled transit time plus at least one day of delay.

How should you ship each type of food?

For shelf-stable product lines, see our guide to shipping snacks and non-perishable foods; for temperature-controlled programs at scale, see cold chain fulfillment.

What are the USPS rules for shipping food with dry ice?

Dry ice is frozen carbon dioxide (UN1845). It keeps food far colder than gel packs and turns into gas instead of melting, which is why it is regulated as a hazardous material. Under USPS Publication 52 (Packaging Instruction 9A):

• Air transportation (Priority Mail Express, Priority Mail, First-Class Mail): no more than 5 pounds of dry ice per package, a Class 9 hazard label, and the marking "Dry Ice, UN1845" or "Carbon Dioxide Solid, UN1845".
• Surface transportation (USPS Ground Advantage, Parcel Select): more than 5 pounds is allowed; mark the box "Surface Only" plus the UN1845 marking.
• Every package must show what is being cooled and the net weight of the dry ice, and use a container that lets carbon dioxide gas escape. Never seal dry ice in an airtight container.
• International mail: dry ice is prohibited.

Source: USPS Publication 52, Packaging Instruction 9A. UPS and FedEx publish their own dry-ice requirements, so check the current guide for whichever carrier you use before your first shipment. USDA also recommends writing "Contains Dry Ice" on the outside of the box and keeping dry ice from touching the food directly.

How do you pack perishable food so it stays cold?

1. Pre-chill or freeze the product before it goes in the box. Coolant maintains temperature; it does not bring warm food down.
2. Seal the food in vacuum bags or leak-proof liners so condensation or thaw can't leak through the carton.
3. Use an insulated container (molded foam cooler or insulated liner) inside a corrugated outer box.
4. Add coolant on top and around the product: gel packs for refrigerated items, dry ice for frozen. Fill empty space so cold air isn't displaced.
5. Label it: "Perishable", "Keep Refrigerated/Frozen", and the dry-ice markings above when they apply.
6. Ship Monday to Wednesday and avoid the day before a holiday, so a one-day delay doesn't strand the box in a hub over a weekend.

What is the cheapest way to ship perishable food?

The biggest lever is distance. A box that reaches the customer in one or two days by ground costs far less than overnight air, so shipping from a location close to your buyers matters more than any single carrier discount. Other levers:

• Right-size the cooler. Insulated boxes are bulky and are usually billed on dimensional weight, not actual weight. Our dimensional weight guide shows the math.
• Match coolant to transit. Over-packing dry ice for a one-day trip adds weight and cost; under-packing risks a spoiled order you have to replace.
• Use ground for shelf-stable items. USPS Ground Advantage or UPS/FedEx Ground is enough for anything that doesn't need cold chain.
• Season-proof the lane. Summer lanes into hot states need more coolant or faster service than the same lane in winter.

When should a food brand use a 3PL for shipping?

Once you are packing coolers every day, the work shifts from shipping to cold-chain operations: storage at the right temperature, lot and expiration tracking, coolant inventory and carrier cut-offs. That is the point where food and beverage brands usually move to a 3PL with temperature-controlled space. Atomix Logistics' Milwaukee flagship offers temperature-controlled storage and lot tracking, with fulfillment centers positioned to reach about 80% of the U.S. in two days or less (see Atomix locations). Before choosing any warehouse for food, read what FDA-registered, food-grade storage means, and compare costs on the Atomix fulfillment pricing page.

Frequently asked questions

Can you mail food through USPS?

Yes. USPS accepts shelf-stable, refrigerated and frozen food, but it offers no refrigeration, so the package has to keep itself cold. USPS recommends Priority Mail or Priority Mail Express for items that need to stay cool, and insurance will not pay a claim for food that spoils, even if the package arrived on time.

How much dry ice can you ship with USPS?

Up to 5 pounds of dry ice per package when it travels by air (Priority Mail Express, Priority Mail, First-Class Mail). Surface services such as USPS Ground Advantage and Parcel Select can carry more than 5 pounds. Either way the box must vent gas and be marked "Dry Ice, UN1845" with the net weight, and dry ice cannot be mailed internationally.

What temperature should perishable food arrive at?

USDA guidance is that perishable food should arrive frozen, partially frozen with ice crystals, or at least refrigerator-cold, which means below 40°F measured with a food thermometer. Food that arrives above 40°F should not be eaten, so pack enough coolant to cover the full transit time plus a delay buffer.

What is the cheapest way to ship perishable food?

Ship from a location close to your customers so a 1-2 day ground service can replace overnight air, use the lightest insulation that still holds temperature, and ship early in the week so boxes never sit over a weekend. Oversized coolers are billed on dimensional weight, so right-sizing the box often saves more than switching carriers.

Can you ship frozen food without dry ice?

Only for short trips. Frozen gel packs can keep frozen food solid for roughly a day in a well-insulated box, which can work for overnight delivery to nearby zones. For two-day transit or hot-weather lanes, dry ice is the dependable option, because it stays far colder than gel packs and sublimates instead of melting.