Flying with dry ice: carry-on and checked baggage rules
You can fly with dry ice in the United States, in carry-on or checked baggage, if you stay within one federal limit and get your airline's approval. The limit is 2.5 kg (5.5 pounds) per person. The package must be vented, and in checked baggage it must be marked.
This guide is for passengers. Dry Ice Wizard itself is a tool for FedEx, UPS, and USPS shipments; it does not produce airline baggage paperwork. If you need to move more dry ice than a passenger may carry, shipping it is the alternative, and that is covered at the end.
The Rules at a Glance
| Carry-on | Checked baggage | |
|---|---|---|
| Quantity | 2.5 kg (5.5 lb) per person | 2.5 kg (5.5 lb) per person |
| Airline approval | Required | Required |
| Vented package | Required | Required |
| Marking | Not specified in the federal rule | "Dry ice" or "Carbon dioxide, solid", plus the net weight or a note that it is 2.5 kg (5.5 lb) or less |
| What it may cool | Perishables that are not hazardous materials | Perishables that are not hazardous materials |
Where the Limit Comes From
The rule is 49 CFR 175.10(a)(10), part of the U.S. hazardous materials regulations. It lists items passengers and crew may carry without following the full regulations, as long as the stated conditions are met. For dry ice the conditions are:
- Approval of the operator. The airline has to agree.
- No more than 2.5 kg (5.5 pounds) per person, when used to pack perishables that are not themselves subject to the hazardous materials regulations.
- The package must permit the release of carbon dioxide gas.
- In checked baggage, each package is marked "DRY ICE" or "CARBON DIOXIDE, SOLID" and marked with the net weight of dry ice or an indication that the net weight is 2.5 kg (5.5 pounds) or less.
The FAA's PackSafe page for dry ice repeats these conditions. It gives the quantity limit as 2.5 kg (5.5 lbs) per package and per passenger, and says packages must not be airtight.
Airline Approval
Approval is a condition of the rule, not a courtesy. TSA's entry for dry ice lists both carry-on and checked bags as "Check with Airline" and says airline approval is required. Contact the airline before you travel and ask what it needs from you. Because approval is the airline's to give, it can decline or add conditions of its own.
TSA also notes that the final decision on whether an item is allowed through the checkpoint rests with the TSA officer.
Venting
Dry ice turns into carbon dioxide gas as it warms. In a container that cannot release the gas, pressure builds and can rupture it. The rule and the FAA both require a package that lets the gas out:
- Do not seal dry ice in an airtight container.
- Carbon dioxide gas is denser than air and can displace oxygen in confined spaces.
- Dry ice is about -79 °C (-110 °F) and can cause severe burns on direct contact with skin.
Marking Checked Baggage
For checked baggage, mark each package containing dry ice with:
- The words "Dry ice" or "Carbon dioxide, solid"
- The net weight of the dry ice, or a statement that it is 2.5 kg (5.5 lb) or less
The federal rule states the marking requirement for checked baggage only. Ask your airline whether it wants a carry-on package marked the same way.
The passenger rule does not call for a Class 9 hazard label or the number UN1845. Those belong to cargo shipments, which follow different rules.
Gel Packs and Other Coolants
The FAA notes that non-hazardous ice packs, such as blue ice and gel packs, can be used alongside dry ice. In carry-on baggage, a pack containing more than 100 ml (3.4 oz) of liquid or gel must be frozen solid when you go through security screening.
How Much Is 2.5 kg?
The limit is the weight of the dry ice itself, not the cooler or its contents. It is not much: FedEx's shipping guidance suggests at least 5 to 10 pounds of dry ice for every 24 hours in transit, so 5.5 pounds is at the low end for a full day. Plan around the limit, not around what the trip would ideally need.
If You Need More Than 2.5 kg
The passenger rule has no higher tier. More dry ice than that has to travel as a shipment, where package limits are much higher:
- FedEx lists a maximum of 200 kg of dry ice per package.
- UPS accepts more than 2.5 kg per package by domestic air with an acceptance audit.
- USPS allows up to 5 pounds per mailpiece by air.
Shipments need what baggage does not: a Class 9 label, the UN1845 marking, and carrier-specific documentation. Dry ice weight limits by carrier compares the three.
Shipping Instead? Generate the Labels
Dry Ice Wizard checks a FedEx, UPS, or USPS dry ice shipment and generates the Class 9 label, the UN1845 outer marking with your net weight, and an acceptance checklist. It covers carrier shipments only. For baggage, the airline's approval and the marking described above are what you need.
Sources
- 49 CFR 175.10(a)(10), exceptions for passengers and crewmembers
- FAA PackSafe: Dry ice
- TSA What Can I Bring: Dry ice
- USPS Publication 52, section 349.31 (hazards of dry ice)
- FedEx: How to ship with dry ice
Important Notes
- This guide is informational and not legal advice. It describes U.S. federal rules. Airlines and other countries can be stricter, so confirm with your airline before you fly.
- Requirements may change. The rules referenced in this guide were last reviewed in October 2026.
- These rules cover dry ice packed with ordinary perishables. Dry ice cooling hazardous materials is outside the passenger exception.
Last updated: October 2026 | dryicecompliance.com