How To Ship Liquids: Carrier Rules for Shipping Liquids

Shipping liquids is logistically more challenging than shipping solid merchandise. For one thing, liquids are heavy, and they can easily spill or leak. And, if there’s a spill or leak, it can lead to an inferior customer experience and cost your business.

Also, many liquids are corrosive, toxic, or flammable—or all three—and this makes some shipping companies reluctant to transport them.

Yet businesses large and small successfully ship liquids to every corner of the globe using some of the world’s biggest cargo companies. Here’s an overview of liquid shipments via the major carriers, plus tips for safely and efficiently packaging liquids.

Can you ship liquids?

Yes, you can ship liquids as an ecommerce merchant. However, shipping liquids is not as straightforward as shipping a solid item, due to the potential for leaks, spills, and the hazardous nature of some liquids. To ship liquids safely, you must pay careful attention to regulations, secure proper packaging, and adhere to carrier guidelines.

Liquids that may be restricted or otherwise regulated

Many liquids are classified as hazardous materials (HAZMAT) and are heavily regulated by government bodies (e.g., the US Department of Transportation) and shipping companies like USPS, FedEx, UPS, and DHL. According to the Department of Transportation, HAZMAT liquids include:

• Flammable liquids. This category includes nail polish, perfumes, and paint thinners, each of which is considered a hazardous material. 

• Alcoholic beverages. Shipping alcohol is legal in some regions and DTC alcohol sales are growing, but it requires proper licensing and an adult’s signature on delivery, among other regulations. Other regions don’t allow direct alcohol shipments to consumers, instead requiring manufacturers to ship alcohol to licensed retailers. Note that alcohol regulations may also apply if you ship hand sanitizer, which uses alcohol as its active ingredient.

• Aerosol cans. Aerosols and other liquids in pressurized containers have to be labeled as hazardous, even if they contain non-hazardous liquids.

• Perishable liquids. This category covers perishable products such as milk, fresh juice, and certain refrigerated supplements. Like all perishable items, these require temperature-controlled shipping. Sometimes, you can ship them in a simple styrofoam cooler with cold packs, but in other situations, you may need to use dry ice.

• Toxic liquids. This includes acids, bleaches, and any other liquids that can cause illness, injury, or death when inhaled, ingested, or absorbed through the skin. In most instances, only certified hazardous materials shippers can transport toxic liquids.

Procedures for dangerous goods shipping vary by carrier.

Carrier rules for shipping liquids

• USPS
• UPS
• FedEx

Whether you’re mailing liquids for your business or shipping them in a personal capacity, you have multiple options when it comes to carriers. However, each major shipping company has strict regulations that apply to domestic shipping. If you ship liquids internationally, you will also be subject to regulations in the destination country.

Here are the key rules and regulations for sending liquids via USPS, UPS, and FedEx:

USPS

The US Postal Service, or USPS, lets customers ship non-hazardous liquids, creams, and pastes, provided they are mailed in sealed, watertight containers to prevent leakage and damage. Here are some specific USPS guidelines for packaging liquids:

• Packaging. All liquids must be in a sealed, leak-proof container with a secure outer container. For a liquid container larger than four ounces, ship it in a triple pack with absorbent material between each layer. If the container is made of metal, you can bypass this rule.

• Labeling. You must place your package in a waterproof container labeled “LIQUID” with orientation arrows showing which end should face up.

• Prohibited items. USPS forbids shipping hazardous materials such as gasoline, paint thinners, and alcohol-based perfumes. You also cannot mail alcoholic beverages via USPS.

UPS

UPS ships a wider array of liquids than USPS does. However, the carrier imposes an array of rules on its customers:

• Packaging. You must ship your liquid in leakproof sealed containers, wrapped in absorbent material in case of leakage. UPS encourages multiple layers of packing materials, with cushioning such as bubble wrap, packing peanuts, packing paper, and air-filled plastic bags.

• Labeling. UPS, similar to USPS, encourages you to place orientation arrows or a “This Side Up” label on your outer packaging. You must also include a warning label when shipping flammable materials.

• Prohibited items. UPS ships a wider array of liquids than USPS. This includes flammable liquids like gasoline, propane, perfumes, and essential oils. You can also ship alcohol via UPS if you obtain the proper licenses and sign shipping agreements. This only covers domestic shipments; many countries will not allow small-batch shipments of alcohol or flammable substances.

FedEx

FedEx uses largely the same guidelines as UPS. FedEx delivery services range from shipping by truck via FedEx Ground to air freight with FedEx Priority. As a general rule, FedEx Ground is the most lenient, although air-shipped packages have more restrictions:

• Packaging. As with UPS and USPS, liquid containers must be leakproof, such as with a screw-on cap. You must also tape the enclosure shut. FedEx encourages wrapping in multiple layers with absorbent materials inserted into the empty spaces between layers. Breakable containers, such as a glass perfume bottle, should be wrapped in shock-absorbing material like bubble wrap. Temperature-sensitive liquids should come wrapped in insulating materials.

• Labeling. Hazardous or flammable liquids must be labeled on the outer packaging. Alcohol shipments must be labeled appropriately and require an adult’s signature for delivery.

• Prohibited items. FedEx is among the most permissive of the major shippers. It allows shipments of flammable liquids via its FedEx Express Dangerous Goods program, but customers must be certified and follow all the regulations with respect to packaging, labeling, and documentation. It also allows alcohol shipments with a FedEx account and proper licenses.

How to ship liquids

1. Use leakproof containers
2. Double seal your packages
3. Fill your package with absorbent materials
4. Choose sturdy outer packaging
5. Follow carrier regulations
6. Consider custom packaging

No matter what carrier you choose, take extra precautions with liquids that wouldn’t be necessary with solid merchandise. Here are seven essential tips to help ensure safe shipping of your liquid cargo:

1. Use leakproof containers

Ensure the original container is leakproof and durable enough to withstand transit. If the original container is flimsy, consider repacking the liquid into a sturdier one.

2. Double seal your packages

Apply a double seal to any liquid container. Tightly close the lid, then reinforce it with waterproof tape or shrink wrap. For added protection, wrap the container in plastic bags to contain any leakage before it damages other items in your package or other shipments from postal customers.

3. Fill your package with absorbent materials

Surround the primary container with highly absorbent materials like vermiculite, sawdust, paper towels, or cotton balls. This material should be sufficient to absorb the entire liquid contents of the container if it were to break. 

4. Choose sturdy outer packaging

For security and durability, use a cardboard box strong enough to protect the liquid container from external impacts and pressure. Avoid using old, damaged, or thin boxes that offer inadequate protection. Ideally, the box should allow for at least two inches of cushioning material on all sides of the liquid container. If shipping multiple bottles, use dividers or individual compartments to prevent contact with other containers that might cause breakage.

5. Follow carrier regulations

Each carrier (USPS, UPS, FedEx, etc.) has detailed rules for shipping various types of liquids, particularly for flammable or corrosive liquids or alcoholic beverages. Some liquids might be prohibited, while others require special certifications, packaging, or shipping (e.g., ground service only). Liquids shipped internationally are subject to the rules and regulations of the recipient’s country.

6. Consider custom packaging 

If shipping liquid containers is a part of your business, you may want to invest in custom containers that snugly hold the vessels you send to customers. This could include custom-molded inserts, foam cutouts, or specialized boxes made specifically for your business. While you may pay more upfront, custom packaging can reduce breakage, leading to greater customer satisfaction and fewer damage claims.