Freight Class for Plastics
Plastic resin is dense freight. A resin maker's data sheet stacks 50 bags of 25 kg on one wooden pallet, 1,250 kg (2,756 lb) of resin. Built up to about 5 feet tall, that pallet measures more than 35 lb/ft³ from the resin alone, which is class 55. Built taller, it drops to class 60 or 65. Finished plastic goods are different: solid parts can be dense, but bins and totes hold a lot of air, so measure each load.
How resin is packed
Most plastic resin leaves the plant as pellets in bags. SOCAR Polymer's data sheet for its HM 0656 EX polyethylene says the pellets are packed in polyethylene bags of 25 kg each, with 50 bags stacked on a flat wooden pallet of 1100 × 1300 × 150 mm. That makes 1,250 kg of resin per pallet, wrapped in stretch-hood film.
Some buyers take resin in big bags instead. The same sheet offers a big bag of about 1,000 kg on a 1140 × 1140 × 150 mm pallet. A 25 kg bag weighs 55.1 lb, so a 50-bag pallet carries 2,756 lb of resin before you add the pallet.
Worked examples
The bag count, net weight and pallet size come from SOCAR Polymer's data sheet for its HM 0656 EX polyethylene. The heights are examples we chose. Density uses the resin weight only; the pallet's own weight would push it a little higher.
50 bags of resin, built 55 inches tall — class 55
50 × 25 kg bags (2,756 lb of resin) on SOCAR's 1100 × 1300 mm pallet, 55 in tall from the floor.
43.3 × 51.2 in = 2,216.5 in². × 55 in ÷ 1,728 = 70.6 ft³. 2,756 lb ÷ 70.6 ft³ = 39.1 lb/ft³.
39.1 lb/ft³ → class 55 (35 to under 50).
The same 50 bags, built 70 inches tall — class 60
The same 2,756 lb of resin, stacked to 70 in from the floor.
2,216.5 in² × 70 in ÷ 1,728 = 89.8 ft³. 2,756 lb ÷ 89.8 ft³ = 30.7 lb/ft³.
30.7 lb/ft³ → class 60. Above about 61 inches the pallet leaves class 55.
One 1,000 kg big bag, 65 inches tall — class 65
A 1,000 kg (2,205 lb) big bag on SOCAR's 1140 × 1140 mm pallet, 65 in tall from the floor.
44.9 × 44.9 in = 2,014.4 in². × 65 in ÷ 1,728 = 75.8 ft³. 2,205 lb ÷ 75.8 ft³ = 29.1 lb/ft³.
29.1 lb/ft³ → class 65 (22.5 to under 30).
When plastic is hazmat
Ordinary resin pellets are not dangerous goods. The Hazardous Materials Table has just two plastic entries. Plastic molding compound in dough, sheet or extruded rope form that gives off flammable vapor is UN3314. Expandable polymer beads that give off flammable vapor, such as raw expandable polystyrene beads, are UN2211. Both are Class 9, packing group III.
So check section 14 of the safety data sheet before you book. If it lists UN3314 or UN2211, the shipment needs hazmat shipping papers and markings. If it says not regulated, it ships as general freight.
Keep it dry and out of the heat
SOCAR Polymer asks for its bags to be stored in a closed, dry place out of direct sun, at least 1 meter from heaters, between -15 °C and 35 °C. Ask for a covered dock and do not leave resin pallets standing in the sun.
Torn bags spill pellets onto other freight and the trailer floor. Check bags at pickup, keep the stretch hood whole and note any damage on the delivery receipt.
Finished plastic goods
Once plastic is molded, the class depends on the shape. Solid parts packed tight can be dense. Bins, totes, buckets and tubs hold air by design, so the same weight takes far more space. Nesting them inside each other and strapping the stacks is the cheapest way to raise density.
Do not put light hollow goods on the same pallet as resin bags. The carrier rates the whole pallet, so a few airy items on top lower its density and can cost a class.
Check your plastics pallet
Enter the pallet's outside size, from the floor to the top of the stack, and its total weight with the pallet. A full pallet of bagged resin will usually show class 55 to 65.
Density-based estimate. Some commodities carry a fixed NMFC class — check our freight class by commodity pages.
Estimated Freight Class
Density
42.51
lb/ft³
Volume
53.33
ft³
Weight
2,267
lb
35–50 lb/ft³ → Class 55
NMFC density scale (Docket 2025-1, effective July 19, 2025)
Free PDF includes a watermark. Pro removes it & adds your brand.
Estimates only — verify freight class/NMFC and chargeable weight with your carrier.
Uses the 13-tier NMFC density scale (Docket 2025-1). See the full freight class chart.
Frequently asked questions
What freight class is plastic resin?
Usually class 55 to 65 for a full pallet of bagged pellets. In SOCAR Polymer's spec, 50 bags of 25 kg make 1,250 kg on a 1100 × 1300 mm pallet. That pallet stays at 35 lb/ft³ or more, class 55, until it is built taller than about 61 inches.
How many 25 kg bags of resin go on a pallet?
SOCAR Polymer stacks 50 bags of 25 kg on a 1100 × 1300 × 150 mm wooden pallet, 1,250 kg net, under a stretch hood. Other makers use other patterns, so check your supplier's data sheet.
Is plastic resin hazmat for shipping?
Plain polyethylene or polypropylene pellets are not listed in the Hazardous Materials Table. Two plastic entries are: plastic molding compound that gives off flammable vapor (UN3314) and expandable polymer beads (UN2211), both Class 9. Check section 14 of the product's safety data sheet.
What freight class are plastic bins and totes?
There is no single class. Hollow goods like bins and totes are mostly air, so they rate higher than resin, and nesting them inside each other can lower the class a lot. Measure the loaded pallet and enter it in the calculator.
What is a big bag of resin?
A large bag that holds about 1,000 kg of pellets on one pallet. SOCAR Polymer packs them on a 1140 × 1140 × 150 mm pallet, without stretch-hood film, when a customer asks for it.