Shipping frozen foods is a growing need for many businesses across various industries. Whether you‘re an artisanal ice cream maker, a meal delivery kit service, a specialty meat provider, or a biotech company needing to transport biological samples, being able to safely and reliably ship frozen goods is crucial to your success.
In 2020 alone, over 230 million shipments of frozen food moved through the U.S. shipping system, representing a market value of $65.1 billion.[^1] This figure is only expected to rise, with the global cold chain market projected to reach $340 billion by 2025, growing at a CAGR of 10.8% from 2020 to 2025.[^2]
While shipping frozen items can seem daunting, it is very much possible to do so using the U.S. Postal Service (USPS). In this comprehensive guide, we‘ll break down everything you need to know to ship frozen foods successfully with USPS from a retail and consumer expert perspective.
Can You Ship Frozen Food with USPS?
Yes, USPS does allow you to ship frozen items domestically via air and ground services as long as your frozen goods are packaged properly. However, USPS does not offer refrigerated shipping services, so the onus is on you as the shipper to ensure your items remain frozen in transit using appropriate insulated containers and refrigerants.
It‘s important to note that USPS cannot guarantee your items will stay fully frozen and they are not liable for spoilage due to thawing. But by following frozen shipping best practices and USPS regulations, which we‘ll outline below, you can greatly increase the odds of your frozen foods arriving intact.
Choosing the Right USPS Service for Frozen Shipments
To keep your frozen items from thawing, you‘ll want to opt for the quickest shipping methods available that minimize the time your package spends in transit. Here are the top USPS services for perishable frozen goods, along with average delivery times:
| Service | Speed |
|---|---|
| Priority Mail Express | Overnight to most locations, 1-2 days to all |
| Priority Mail | 1-3 business days |
| First-Class Package Service (under 1 lb only) | 1-3 business days |
Priority Mail Express is the fastest option, with guaranteed overnight delivery to most U.S. addresses and flat-rate packaging options. Packages sent via this service travel on passenger airlines rather than by truck. Sunday and holiday delivery are also available for an added fee in many locations.
If a 1-3 day delivery window is acceptable for your frozen items, Priority Mail offers more affordable rates than Express. Over 97.7% of Priority Mail packages are delivered within the 1-3 day service standard.[^3] Like Express, Priority Mail has flat-rate box options where you pay one rate regardless of weight or destination.
For frozen packages weighing less than 1 lb, First-Class Package service is another economical 1-3 day option with rates starting at $4.50. However, avoid using First-Class for packages over 1 lb as they‘ll be subject to longer delivery times of 2-5 days.
Ground shipping services like Parcel Select and USPS Retail Ground are not advisable for frozen shipments as transit times can exceed a week, making thawing much more likely.
Using Dry Ice for Frozen Food Shipping
Dry ice is one of the most effective ways to keep your frozen foods cold during shipping. This frozen form of carbon dioxide maintains extremely low temperatures around -109°F (-78°C). As it sublimates into a gas, it keeps your items colder far longer than regular ice without getting your package wet.
However, dry ice is considered a hazardous material due to the risks of frostbite and asphyxiation in enclosed spaces. Shipping with dry ice is subject to strict USPS regulations:
- Dry ice packages are limited to 5 lbs per box for domestic air transport (Priority, Express, First-Class). Larger quantities must go by surface transport only.
- Containers and outer packaging must allow for release of carbon dioxide gas. Airtight containers can rupture from gas buildup.
- All packages containing dry ice must be labeled with "Carbon Dioxide Solid" or "Dry Ice" and include the net weight of dry ice.
- Dry ice air shipments must additionally have a Class 9 DOT miscellaneous hazardous material warning label and a complete shipper‘s declaration for dangerous goods form.
- Dry ice is not permitted in international mail shipments.
In general, you‘ll need about 5-10 lbs of dry ice per 24 hours for every 15 lbs of frozen food, depending on the insulation of your container.[^4] Dry ice will keep items frozen below 32°F for around 18-36 hours in a small styrofoam cooler, or longer in higher quality insulated containers.
If the hazmat regulations for dry ice seem too onerous for your needs, gel packs are a simpler and safer frozen shipping alternative. While gel packs won‘t keep items quite as cold as dry ice, they can still maintain freezing temperatures of 32°F for 24-36 hours, which is sufficient for many frozen goods.
How to Properly Pack Frozen Items for USPS Shipping
The key to ensuring your frozen foods arrive still frozen is proper packaging. Regular cardboard boxes simply won‘t cut it – you need insulated containers and refrigerants to lock in the cold. Here‘s a step-by-step rundown of frozen food packaging best practices:
-
Choose an insulated shipping container. Thick styrofoam coolers (minimum 1.5" wall thickness), insulated liners, and specialty shippers like the Polar Tech Thermo Chill are far more protective than plain boxes. The better insulated, the less refrigerant needed.
-
Line the insulated box. Adding a mylar foil or plastic liner inside the styrofoam provides an extra waterproof barrier in case of any thawing. You may also want to include pads to absorb condensation.
-
Add your pre-frozen items. Your food should already be frozen solid before packing. Place items inside a zip-top bag to protect against moisture and place the sealed bag in the insulated container.
-
Pack with dry ice or gel packs. Surround your bag of frozen food with your refrigerant of choice. For a 7 lb package with a 1.5" thick styrofoam cooler, you‘ll need around 5 lbs of dry ice to maintain freezing for 1 day, or 10 lbs for 2 days.[^4] If using gel packs, use 1 lb of gel packs per 3 lbs of food as a rule of thumb.
-
Seal the container. Securely close the insulated container while allowing for venting if using dry ice. Place inside a sturdy outer box if not using a shipping cooler. Label the box with "Perishable", "Keep Frozen", and any required hazmat labels for dry ice.
-
Ship your package ASAP. Drop off or schedule a pickup for your frozen package as close to the shipping deadline as possible to minimize time spent at room temperature. Avoid shipping over weekends or before holidays that may delay delivery.
Frozen Food Shipping Costs with USPS
The cost of shipping frozen items with USPS will vary based on your package‘s size, weight, destination, shipping speed, and dry ice or gel pack quantities. On average, you can expect to spend anywhere from $30 to $150 or more on a frozen food shipment.
Let‘s look at a cost comparison for shipping a 7 lb frozen food package in a 12" x 9" x 6" styrofoam cooler with 5 lbs of dry ice from Los Angeles to New York City with various USPS services:
| Service | Delivery Time | Price |
|---|---|---|
| Priority Mail Express | 1-2 days | $126.10 |
| Priority Mail | 2-3 days | $21.10 |
| Parcel Select Ground | 2-8 days | $21.93 |
*Rates sourced from USPS.com in March 2023 and include $3.15 dry ice surcharge. Flat-rate options not used due to package size limit.
As you can see, Priority Mail Express is by far the priciest frozen shipping option at $126.10, but provides swift guaranteed 1-2 day delivery. Priority Mail is a more affordable $21.10 for 2-3 day service. Ground shipping costs about the same as Priority Mail, but with a much longer delivery window that risks thawing.
These base rates do not include the costs of packaging materials like insulated containers, dry ice, and gel packs, which can add $10-50 or more per shipment.
If you‘re shipping frozen items regularly, buying supplies in bulk can provide significant savings. ULINE, for instance, sells 15" x 11" x 11" styrofoam coolers for $22.20 each if buying a case of 6, versus $31 each if purchasing singly.[^5]
Key Tips for Successfully Shipping Frozen Food via USPS
Shipping frozen items is not without risks and challenges, but implementing these expert tips can greatly improve your odds of frozen foods arriving fully frozen:
- Invest in high-quality insulated containers rated for frozen shipping. The better the insulation, the longer your foods will stay frozen.
- Use enough dry ice or gel packs to maintain freezing temps for twice your expected transit time in case of delays. Around 5-10 lbs of dry ice or 1 lb of gel packs per 3 lbs of food is a good rule of thumb.
- Choose expedited 1-3 day services like Priority Mail Express or Priority Mail and avoid ground shipping. Every extra day in transit is more time for thawing to occur.
- Follow all USPS guidelines for shipping with dry ice including proper labeling, packaging, and hazmat regulations.
- Plan your shipping days carefully. Aim for your package to arrive by Friday if possible. Avoid dropping off frozen items before weekends or holidays that could extend transit times.
- Communicate to customers that some thawing may occur in transit despite precautions, and that they should refrigerate or freeze items immediately upon receipt.
- Research destination-specific shipping restrictions and total transit times, especially for international frozen food shipping which is more complex.
- Always include "Perishable" and "Keep Frozen" labels on your packages to alert carriers to special handling requirements.
- Test your frozen shipping packaging under real-world conditions. Send a test package to yourself, noting any thawing and adjust your packing and refrigerant as needed.
- Consider third-party frozen shipping services like Penguin Pack or Dry Ice Corp if your frozen shipping needs become too complex or higher volume.
By implementing these frozen shipping best practices, you‘ll be well on your way to mastering the art of sending frozen goods through USPS. With the proper packing and the swift delivery options like Priority Mail Express, your frozen foods should reach their destination still frozen and ready to enjoy.
The Bottom Line
Shipping frozen food items with USPS is very doable with the right packing methods and service choices. By using insulated containers, ample refrigerants like dry ice or gel packs, and expedited 1-3 day delivery options, your frozen foods can safely reach their destination still frozen solid.
While not without added costs and potential risks, being able to effectively ship frozen items opens up a whole new realm of possibilities for your business, whether you‘re shipping direct to consumers or other businesses.
As the market for mail-order frozen goods continues to grow, being an early master of frozen shipping best practices can give you a competitive edge. Don‘t be afraid to test and refine your frozen shipping methods until you‘ve optimized a system that works smoothly and consistently for your unique frozen products.
With this complete guide and expert tips in hand, you should be ready to conquer the challenges of shipping frozen food with USPS. May your frozen shipments always arrive icy cold!
References
[^1]: Shipping Frozen Food Statistics and Facts[^2]: Cold Chain Market Worth $340.3 Billion by 2025
[^3]: USPS Service Performance Results
[^4]: How Much Dry Ice Do You Need for Shipping?
[^5]: Styrofoam Shipping Coolers – ULINE
