How to Ship Perishable Food: 7 Steps for Safe Delivery

To ship perishable food, pack it in an insulated cooler inside a sturdy corrugated box, surround it with frozen gel packs (for chilled food) or dry ice (for frozen food), and send it by an overnight or 2-day service early in the week so it arrives before the coolant runs out. Both USPS and UPS accept perishables at the sender’s risk, and both allow dry ice as a refrigerant if the box can vent and is marked correctly.

The seven steps below cover what can legally go in the mail, how to choose coolant and insulation, which USPS and UPS services are fast enough, and how to label a dry ice package. When you’re ready to price a box, compare overnight and 2-day USPS and UPS rates in the ParcelPath rate calculator.

What are the carrier rules for shipping perishable food?

USPS defines perishables as items that can deteriorate in the mail, such as food, plants and live animals. Permissible perishables are “sent at the mailer’s own risk” and must be packaged and mailed so they arrive before they begin to deteriorate, and USPS adds an extra handling fee for them that varies by service. USPS Publication 52 adds three rules that matter for food:

• Foods that spoil easily are nonmailable if they decompose easily or can’t reach their destination without spoiling.
• Fresh fruits and vegetables must be dry, meaning not wet or dripping, to be mailable.
• Meat and meat products are mailable domestically only when they comply with USDA regulations, and the packaging must meet USPS strength and sealing requirements.

UPS also carries perishables, but like USPS it treats spoilage from delay as the shipper’s risk, which is why packaging and service choice do most of the work. Our guide Can You Send Food in the Mail? covers which everyday foods ship easily and which don’t.

How do you ship perishable food, step by step?

Step 1: Decide whether the food needs cold, frozen or no coolant

Sort what you’re sending into three groups. Food that must stay chilled, such as meat, seafood, dairy and prepared meals, should stay at 40°F or below, the USDA’s refrigeration guideline. Frozen food should stay at 0°F or below. Shelf-stable items like most baked goods, jerky and hard cheese don’t need coolant and can go by a slower, cheaper service.

Step 2: Pre-chill or freeze the food before packing

Packaging keeps food cold; it doesn’t make food cold. Refrigerate chilled items overnight and freeze frozen items solid before they go in the box. Vacuum-seal or double-bag meat and seafood so juices can’t leak, and wrap anything wet in a food-grade plastic liner.

Step 3: Use an insulated container inside a corrugated box

An expanded polystyrene (foam) cooler is the standard choice, and thicker walls hold temperature longer. Insulated liners and recyclable insulated boxes work for shorter trips. Always put the cooler inside a strong corrugated outer box, because a foam cooler on its own can crack in handling. Our roundup of cold shipping boxes compares the main options.

Fill empty space with crumpled paper or more coolant. Air gaps warm up quickly, and a snug fit also stops the contents from shifting and crushing.

Step 4: Choose and place the coolant

Gel packs are right for refrigerated food. Freeze them solid, then place them on top of and around the food, since cold air sinks. Avoid loose wet ice, which melts, leaks and can get a box rejected.

Dry ice is frozen carbon dioxide at about -109°F, and it’s the only practical way to keep food frozen for a day or more. Don’t let it touch the food directly, never seal it in an airtight container, and handle it with gloves. As it sublimates it releases carbon dioxide gas, so the package has to vent.

Step 5: Pick a service fast enough for the coolant

The service has to beat the coolant. For most chilled and frozen food that means overnight or 2-day delivery, and for shorter distances a 1-to-3-day service can work in cool weather.

Ship Monday through Wednesday so the box isn’t sitting in a warehouse over the weekend, and avoid shipping just before a holiday. If the recipient has a P.O. Box, only USPS can deliver there, so our guide on how to ship to a P.O. Box explains your options. For more on fast services, see our comparison of overnight shipping options.

Step 6: Label the box correctly, especially with dry ice

Mark every perishable box “Perishable” and “Keep Refrigerated” or “Keep Frozen,” and add “This Side Up” arrows so the coolant stays on top. Dry ice adds legal requirements. Under USPS Packaging Instruction 9A:

• Every dry ice package must be marked with the name of the contents being cooled (for example, “frozen steaks”) and the net weight of the dry ice.
• Air shipments, which include Priority Mail Express and Priority Mail, may hold no more than 5 pounds of dry ice per package and need a Class 9 hazardous material label and the marking “Dry Ice, UN1845” or “Carbon Dioxide Solid, UN1845.”
• Surface shipments may hold more than 5 pounds but must be marked “Surface Only” with the UN1845 name, and must never move by air.
• Dry ice can’t go in international mail or to APO/FPO/DPO addresses.

UPS also accepts dry ice-packed perishables. UPS air packages need the same UN1845 marking, Class 9 label and net dry ice weight, and UPS limits the amount of dry ice per air package, so check the current limit with UPS before you pack a large frozen order.

Step 7: Track the package and tell the recipient it’s coming

Send the tracking number the moment the label is printed, and ask the recipient to unpack and refrigerate the food as soon as it arrives. If a box is going to a business, confirm someone will be there to receive it. Chilled food that arrives above 40°F, or frozen food that has fully thawed, shouldn’t be eaten.

How should you pack different perishable foods?

Each category has its own weak point, so adjust the method to the food:

• Meat and poultry: freeze solid, vacuum-seal, ship with dry ice by overnight or 2-day service, and keep it in compliance with USDA rules.
• Seafood: the most time-sensitive food. Pack it sealed and leak-proof with plenty of coolant and send it overnight. Our guide on how to ship seafood goes into detail.
• Dairy: soft cheese, milk and yogurt need gel packs and overnight service; aged hard cheese tolerates 2-day transit.
• Produce: ship it dry, in ventilated liners, and keep ethylene producers such as apples and bananas apart from leafy greens.
• Baked goods: most don’t need coolant, but cream fillings and cheesecake do. See how to ship baked goods.
• Coffee and other dry goods: no coolant needed; shipping coffee is about freshness and airtight packaging instead.

For frozen items in particular, our guide to shipping frozen food walks through dry ice quantities and cooler sizes, and the broader perishables and food shipping guide covers every food category we’ve written about.

How can you cut the cost of shipping perishable food?

Overnight service and dry ice are what make perishable shipping expensive, so savings come from using only as much speed and weight as the food needs. Use the smallest cooler that fits, since carriers charge by dimensional weight on bulky boxes. Ship shelf-stable items separately by a slower service, and choose 2-day air over overnight when your coolant comfortably lasts the trip. The shipping calculator guide explains how weight, size and speed drive the price.

With ParcelPath, overnight and 2-day labels cost up to 85% less with UPS and up to 89% less with USPS, and the service is free, with no subscription, per-label fee or minimum. You can schedule free USPS pickups and add Shipsurance coverage to high-value boxes. For pallet-size food orders, PalletPath quotes LTL freight in the ParcelPath freight quote tool, and our article on refrigerated shipping costs explains what drives the price of temperature-controlled freight.

Frequently Asked Questions

Can you ship perishable food through USPS?

Yes. USPS accepts perishable food at the mailer’s own risk, as long as it’s packaged to arrive before it deteriorates. Foods that decompose easily or can’t reach the destination unspoiled are nonmailable, fresh produce must be dry, and meat must meet USDA rules. Priority Mail Express, with overnight to 2-day delivery, is the best USPS choice for chilled food.

Does USPS accept dry ice?

Yes, when dry ice is used as a refrigerant and the package lets carbon dioxide gas escape. Under USPS Packaging Instruction 9A, air packages can hold up to 5 pounds of dry ice and need a Class 9 label and “Dry Ice, UN1845” marking. Every dry ice package must show the net weight of the dry ice, and dry ice can’t go in international mail.

How long can perishable food stay cold in a shipping box?

It depends on the insulation, the coolant and the outside temperature, but most gel-pack shipments are planned for overnight or 2-day transit, and dry ice is needed to keep food frozen beyond a day. Pack enough coolant to cover the delivery commitment plus a day of delay, and ship early in the week to avoid weekend holds.

What is the best way to ship perishable food overnight?

The best way to ship perishable food overnight is a pre-chilled foam cooler inside a corrugated box, with frozen gel packs or dry ice on top, sent by UPS Next Day Air or USPS Priority Mail Express on a Monday through Wednesday. Mark the box “Perishable,” follow the dry ice labeling rules, and send the tracking number to the recipient.

Sources

• USPS: Shipping Restrictions (perishables and dry ice)
• USPS Publication 52, Chapter 5: Perishable Matter
• USPS Publication 52, 53: Fresh Foods and Other Perishables
• USPS Publication 52, 55: Meats and Meat Products
• USPS Publication 52, Packaging Instruction 9A: Dry Ice
• USPS Publication 52, 743: Perishable Matter with Dry Ice

Part of our Perishables and Food guide. Related: How to Ship Frozen Food, Shipping Coffee.