Shipping Liquids: Rules to Know for USPS, UPS, and FedEx | ShippingEasy
shipping liquids with USPS FedEx UPS

Shipping Liquids: Rules to Know for USPS, UPS, and FedEx

By Rob Zaleski, Apr 3, 2019

Many online sellers, particularly those starting out, may not be fully aware of the rules each carrier has when it comes to shipping liquids. Since shipping rates and guidelines are updated each year, things can become difficult to get right. On top of that, Google seems to think that the only liquid people want to ship is alcohol, so that dominates the search results (by the way, we cover that in this support article).

To help merchants who ship liquids often—vendors like vape supplies, CBD oil, essential oils, makeup and beauty supplies, and more—we did some digging ourselves to help you understand the rules to follow when shipping liquids via USPS, FedEx, and UPS.

Rules for FedEx


FedEx does a pretty good job of laying out some of their guidelines for shipping liquids in a step by step fashion, with a helpful graphic below. We’ve pulled some of the most important information from the pdf to feature it in one place for you.

  1. Primary watertight inner receptacle. Use watertight containers for liquid specimens with a positive closure such as a screw-on, snap-on, or push-on lid, taped for an additional seal. If you place multiple fragile primary receptacles in a single secondary receptacle, they must be individually wrapped or separated to prevent contact between them.
  2. Absorbent material. Place absorbent material between the primary and secondary receptacles, using enough material to absorb the entire contents of all primary receptacles. Suggested absorbent materials include cellulose wadding, cotton balls, superabsorbent packets, and paper towels.
  3. Secondary watertight inner receptacle. Use a watertight sealed plastic bag, plastic canister, or screw-cap can.
  4. Sturdy outer packaging. Use rigid outer packaging constructed of corrugated fiberboard, wood, metal, plastic, or other equally strong material, including cylinders made of such materials and appropriately sized for the contents. Chipboard or paperboard boxes, paper envelopes, and plastic bags are unacceptable outer packaging. The completed packaging must be of good quality, strong enough to withstand the normal rigors of transportation without loss of contents as a result of vibration, changes in temperature, humidity, or pressure

shipping liquid with FedEx

Note that there are specific labeling and possibly packaging guidelines if you are shipping human/biological specimens using FedEx. FedEx also prohibits containers of liquids with a volume exceeding 8 gallons (32 liters) or 70 lbs. in weight for FedEx Ground and SameDay City.

Rules for USPS


Nonflammable, nonhazardous liquids can be sent via USPS, if sealed inside a waterproof container. A recently proposed rule change states that mailers must mark the outer container of a mailpiece containing liquid to indicate the nature of the contents, and include orientation arrows. This is regardless of whether the package is deemed “breakable” by the shipper.

If you are shipping liquids in containers greater than 4 oz, you are required to triple pack these containers. This means you need to pad around the original container(s), then surround the original packaging with another sealed, leak-proof container which includes absorbent materials, then have that packing in the rigid packaging noted far above, such as a Priority Mail box, Flat Rate box, or Regional Rate box.

Liquids are also perfect candidates for cubic pricing like ShippingEasy’s Flat Rate Green. This applies to smaller, heavier packages (2 – 20 lbs.). A ShippingEasy customer who sells 6 and 12-packs of vitamin-infused water cut 40% off their shipping budget by switching from FedEx to using Flat Rate Green.

If you ship larger packs of liquid, say, 6 packs or 12 packs, cubic pricing can make your 18 lb. case the same price as a 2 lb. case and save an almost unbelievable amount of money per package.

— Michael Trotzuk, ShippingEasy shipping expert

Remember too, if your package weighs less than 16 oz, you can ship it using First Class Package Service, which allows you to use your own box and is the cheapest method for shipping under 1 lb.

2019
First Class
1 & 2Zone 3Zone 4Zone 5Zone 6Zone 7Zone 8Zone 9
1 oz$2.66$2.68$2.70$2.76$2.84$2.96$3.09$3.09
2 oz$2.66$2.68$2.70$2.76$2.84$2.96$3.09$3.09
3 oz$2.66$2.68$2.70$2.76$2.84$2.96$3.09$3.09
4 oz$2.66$2.68$2.70$2.76$2.84$2.96$3.09$3.09
5 oz$3.18$3.20$3.22$3.28$3.36$3.49$3.63$3.63
6 oz$3.18$3.20$3.22$3.28$3.36$3.49$3.63$3.63
7 oz$3.18$3.20$3.22$3.28$3.36$3.49$3.63$3.63
8 oz$3.18$3.20$3.22$3.28$3.36$3.49$3.63$3.63
9 oz$3.82$3.85$3.88$3.96$4.06$4.19$4.33$4.33
10 oz$3.82$3.85$3.88$3.96$4.06$4.19$4.33$4.33
11 oz$3.82$3.85$3.88$3.96$4.06$4.19$4.33$4.33
12 oz$3.82$3.85$3.88$3.96$4.06$4.19$4.33$4.33
13 oz$4.94$4.98$5.02$5.12$5.24$5.38$5.53$5.53
14 oz$4.94$4.98$5.02$5.12$5.24$5.38$5.53$5.53
15 oz$4.94$4.98$5.02$5.12$5.24$5.38$5.53$5.53
15.999 oz$4.94$4.98$5.02$5.12$5.24$5.38$5.53$5.53

If you’re shipping liquids in primary containers with less than 4 oz of liquids, you recently dodged a bullet. The USPS was considering enforcing the triple packing rule across the board, meaning companies like vape supplies, essential oils, CBD oils, and beauty supplies would have had to invest in more padding and packaging, driving up the cost of shipping these products. For now, USPS has decided to continue monitoring these items and will not make the rule change at this time.

Major 2019 changes: Understand all of the First Class Package service rate changes.

Rules for UPS


UPS doesn’t do a great job of elucidating their specific rules to shipping liquids. It can be inferred from some short mentions on their website that their rules resemble those of FedEx pretty closely. If there’s any uncertainty, it’s always best to reach out to your UPS rep for clarity and ensure your packages arrive as they should.

Once you know the rules, it’s time to automate your shipping processes and have a platform that chooses the right shipping methods automatically for every order. Schedule a demo with one of our shipping experts to see how easy your shipping can be—even if you think you ship a complicated product!

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Rob Zaleski

Content Marketing Manager at ShippingEasy
I'm a digital content and social media nerd with a passion for telling stories, helping connect people, and finding joy in the details.

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