Question 1

When should I use a poly mailer instead of a box?

Accepted Answer

Use poly mailers for soft, flexible, non-fragile goods like clothing, fabric items, towels, and accessories. Mailers conform to the product shape, have minimal DIM weight, and cost $0.10-$0.30 per unit less than boxes. For hard, fragile, or oddly-shaped items that need rigid protection, a box with padding is safer.

Question 2

How much do poly mailers save on shipping?

Accepted Answer

Savings depend on how large the box would have been. For a t-shirt that would otherwise ship in a 12x10x4 box, switching to a poly mailer eliminates DIM weight entirely - the difference can be $2-5 per package with UPS or FedEx. At 500 shipments per month, that is $1,000-$2,500/month in savings.

Question 3

Does DIM weight apply to poly mailers?

Accepted Answer

Poly mailers have negligible DIM weight because they are flat and flexible. A 10x13 mailer containing a t-shirt has a DIM weight well under 1 lb. Actual weight drives the rate, not dimensions. This is the core cost advantage of mailers over boxes for soft goods.

Question 4

What items should not be shipped in poly mailers?

Accepted Answer

Avoid poly mailers for fragile items (electronics, glass, ceramics), hard items that cannot flex, liquids, and anything that needs rigid protection during transit. When in doubt, use a box with padding.

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